diff --git a/package.json b/package.json
index d5cbce6..2026dd6 100644
--- a/package.json
+++ b/package.json
@@ -41,32 +41,32 @@
     "bluebird": "^3.7.1",
     "classnames": "^2.2.6",
     "codecov": "^3.6.1",
-    "gatsby": "^2.17.16",
+    "gatsby": "^2.18.0",
     "gatsby-link": "^2.2.24",
     "gatsby-plugin-catch-links": "^2.1.17",
     "gatsby-plugin-feed": "^2.3.21",
     "gatsby-plugin-flow": "^1.1.14",
     "gatsby-plugin-google-gtag": "^1.1.16",
-    "gatsby-plugin-manifest": "^2.2.28",
+    "gatsby-plugin-manifest": "^2.2.29",
     "gatsby-plugin-netlify": "^2.1.25",
     "gatsby-plugin-netlify-cms": "^4.1.28",
-    "gatsby-plugin-offline": "^3.0.21",
+    "gatsby-plugin-offline": "^3.0.22",
     "gatsby-plugin-optimize-svgs": "^1.0.3",
     "gatsby-plugin-react-helmet": "^3.1.15",
     "gatsby-plugin-sass": "^2.1.23",
-    "gatsby-plugin-sharp": "^2.3.1",
+    "gatsby-plugin-sharp": "^2.3.2",
     "gatsby-plugin-sitemap": "^2.2.21",
     "gatsby-remark-autolink-headers": "^2.1.18",
     "gatsby-remark-copy-linked-files": "^2.1.30",
     "gatsby-remark-external-links": "0.0.4",
-    "gatsby-remark-images": "^3.1.31",
+    "gatsby-remark-images": "^3.1.32",
     "gatsby-remark-katex": "^3.1.17",
     "gatsby-remark-prismjs": "^3.3.23",
     "gatsby-remark-relative-images": "^0.2.3",
     "gatsby-remark-responsive-iframe": "^2.2.27",
     "gatsby-remark-smartypants": "^2.1.16",
-    "gatsby-source-filesystem": "^2.1.37",
-    "gatsby-transformer-remark": "^2.6.36",
+    "gatsby-source-filesystem": "^2.1.38",
+    "gatsby-transformer-remark": "^2.6.37",
     "gatsby-transformer-sharp": "^2.3.5",
     "invariant": "^2.2.4",
     "katex": "^0.11.1",
diff --git a/yarn.lock b/yarn.lock
index 83e698c..9372ccb 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6260,10 +6260,10 @@ fuzzy@^0.1.1:
   version "0.1.3"
   resolved "https://registry.yarnpkg.com/fuzzy/-/fuzzy-0.1.3.tgz#4c76ec2ff0ac1a36a9dccf9a00df8623078d4ed8"
 
-gatsby-cli@^2.8.11:
-  version "2.8.11"
-  resolved "https://registry.yarnpkg.com/gatsby-cli/-/gatsby-cli-2.8.11.tgz#fafe232904183797a829fd94c8f8b54f590cc6c6"
-  integrity sha512-pqgfpdwi8tHqCMJ/DtrBtrc2h48c7AWkLKVklFYX19cKDMyFob3nVasv20l3TqQYDsTlrVz8yBveV06mG4MQCQ==
+gatsby-cli@^2.8.12:
+  version "2.8.12"
+  resolved "https://registry.yarnpkg.com/gatsby-cli/-/gatsby-cli-2.8.12.tgz#e1d870a15258003b3ee6db68a24d5b6bc9d4368d"
+  integrity sha512-PlnkwmUugKSTPiLkGsgDWjevXNVItkRnnouJ++S60DKg3e7TB56Zth+L9XY/4S4IXkjIYnrxgTD98rEPA9M4Lg==
   dependencies:
     "@babel/code-frame" "^7.5.5"
     "@babel/runtime" "^7.7.2"
@@ -6280,8 +6280,8 @@ gatsby-cli@^2.8.11:
     execa "^3.3.0"
     fs-exists-cached "^1.0.0"
     fs-extra "^8.1.0"
-    gatsby-core-utils "^1.0.19"
-    gatsby-telemetry "^1.1.37"
+    gatsby-core-utils "^1.0.20"
+    gatsby-telemetry "^1.1.38"
     hosted-git-info "^3.0.2"
     is-valid-path "^0.1.1"
     lodash "^4.17.15"
@@ -6308,10 +6308,10 @@ gatsby-cli@^2.8.11:
     ink "^2.5.0"
     ink-spinner "^3.0.1"
 
-gatsby-core-utils@^1.0.19:
-  version "1.0.19"
-  resolved "https://registry.yarnpkg.com/gatsby-core-utils/-/gatsby-core-utils-1.0.19.tgz#670a0eefe8fc8517c5b87573be6cd817d4b1a96a"
-  integrity sha512-Fp5PBmAuqL+V5FTqjQ6d2Ow7a9OY6GlJVlS5wl/bbbGjRDtYJe7tqAxWThzeKDkLAsKUz2RP8AiJOSLWn1bDRg==
+gatsby-core-utils@^1.0.20:
+  version "1.0.20"
+  resolved "https://registry.yarnpkg.com/gatsby-core-utils/-/gatsby-core-utils-1.0.20.tgz#f4788c2591fa7165c87f0ee5e8edf664c91978ea"
+  integrity sha512-vdOy/+8UjY3taUEf85s/P8a5qfw4OUTRfvrmwJ8OOBfWkpcJRLEgW2EYfkYfGp3u9l8KKQv4VsdG3XRVQb36KQ==
   dependencies:
     ci-info "2.0.0"
 
@@ -6331,19 +6331,19 @@ gatsby-link@^2.2.24:
     "@types/reach__router" "^1.2.6"
     prop-types "^15.7.2"
 
-gatsby-page-utils@^0.0.30:
-  version "0.0.30"
-  resolved "https://registry.yarnpkg.com/gatsby-page-utils/-/gatsby-page-utils-0.0.30.tgz#dac099d695540f769fafaf156744f6017ea21a59"
-  integrity sha512-dI5K5Q6N5S7SXw4y+8Iu9+60X/orv0SXXxKxvvWHot4CuxHvV4n+nUGyf0dA/87vRBlR6mIncLnSU1JcQr1acg==
+gatsby-page-utils@^0.0.31:
+  version "0.0.31"
+  resolved "https://registry.yarnpkg.com/gatsby-page-utils/-/gatsby-page-utils-0.0.31.tgz#4314675d059627a56cc2ca66e921a5aa105058c0"
+  integrity sha512-PqlcRZr2XBB6dtvhWMMZ0rNmQmZbgt2WijNWPLYceuqQ4GhI2XQaF4WJJvuMu/n6W9Tnr9/wzaDjc7/3KN5tVQ==
   dependencies:
     "@babel/runtime" "^7.7.2"
     bluebird "^3.7.1"
     chokidar "3.3.0"
     fs-exists-cached "^1.0.0"
+    gatsby-core-utils "^1.0.20"
     glob "^7.1.6"
     lodash "^4.17.15"
     micromatch "^3.1.10"
-    slash "^3.0.0"
 
 gatsby-plugin-catch-links@^2.1.17:
   version "2.1.17"
@@ -6380,13 +6380,13 @@ gatsby-plugin-google-gtag@^1.1.16:
     "@babel/runtime" "^7.7.2"
     minimatch "^3.0.4"
 
-gatsby-plugin-manifest@^2.2.28:
-  version "2.2.28"
-  resolved "https://registry.yarnpkg.com/gatsby-plugin-manifest/-/gatsby-plugin-manifest-2.2.28.tgz#17464f404c58b748ebd34efbf783a6f5b0f85f1b"
-  integrity sha512-VvpVF4uE2IkNW+WXN8UvB2slU3tldR054beyvmOAt4HkKgnRLBU8j78yGrEhzdUHqbt2wgroI2KI9VYMiicG4Q==
+gatsby-plugin-manifest@^2.2.29:
+  version "2.2.29"
+  resolved "https://registry.yarnpkg.com/gatsby-plugin-manifest/-/gatsby-plugin-manifest-2.2.29.tgz#f5c4d65c424059007f8c23a49e332436614c03a4"
+  integrity sha512-vLk6kRNzsZ6VVfsZQLHfw14DbVcVG/rAYYCape9kYi7qoV/QNx6NQ6ntD4RmB7FczaLrN7hk8hE2YNuz7DTDVQ==
   dependencies:
     "@babel/runtime" "^7.7.2"
-    gatsby-core-utils "^1.0.19"
+    gatsby-core-utils "^1.0.20"
     semver "^5.7.1"
     sharp "^0.23.2"
 
@@ -6414,17 +6414,17 @@ gatsby-plugin-netlify@^2.1.25:
     lodash "^4.17.15"
     webpack-assets-manifest "^3.1.1"
 
-gatsby-plugin-offline@^3.0.21:
-  version "3.0.21"
-  resolved "https://registry.yarnpkg.com/gatsby-plugin-offline/-/gatsby-plugin-offline-3.0.21.tgz#0fad8f372c6414ab7b3475838729126b13dd49e2"
-  integrity sha512-cCXLqYdRf2CbzJIWprAID27Xo2ZUpgz8ShXLnNC9VYTzop9FHujrJ/YK0v53cR0t8hSQddgkV4VVd/liFZdBBg==
+gatsby-plugin-offline@^3.0.22:
+  version "3.0.22"
+  resolved "https://registry.yarnpkg.com/gatsby-plugin-offline/-/gatsby-plugin-offline-3.0.22.tgz#a8fb03e4d6abbd8cc14a03a9427424734675d484"
+  integrity sha512-gPCBZklh/u4DXqcxdhCd4qPDNUCxp3z0RMH6ZfsL4AfAO4nOsnTdWVW2nr/114jxT7muLSLZUGM5PAXZL/X8aA==
   dependencies:
     "@babel/runtime" "^7.7.2"
     cheerio "^1.0.0-rc.3"
+    gatsby-core-utils "^1.0.20"
     glob "^7.1.6"
     idb-keyval "^3.2.0"
     lodash "^4.17.15"
-    slash "^3.0.0"
     workbox-build "^4.3.1"
 
 gatsby-plugin-optimize-svgs@^1.0.3:
@@ -6435,15 +6435,15 @@ gatsby-plugin-optimize-svgs@^1.0.3:
     svgo "^1.3.0"
     walk "^2.3.14"
 
-gatsby-plugin-page-creator@^2.1.30:
-  version "2.1.30"
-  resolved "https://registry.yarnpkg.com/gatsby-plugin-page-creator/-/gatsby-plugin-page-creator-2.1.30.tgz#ee57c6a8ac4cdbed7fa3ae99e6ada0df427d7fed"
-  integrity sha512-2ChRSqj+NoKxTyk+U/0SpRpV2l7unb+xbhnV4uxlfjtCY9xo6/ysj4NnAwX8uY2WgY5zA1bDNiS+3zASN692+Q==
+gatsby-plugin-page-creator@^2.1.31:
+  version "2.1.31"
+  resolved "https://registry.yarnpkg.com/gatsby-plugin-page-creator/-/gatsby-plugin-page-creator-2.1.31.tgz#21554d125d5bd333b5307ea12ece7da297a8eb89"
+  integrity sha512-eDrEGGVOZ042QLiCM7qmh6AyC7ODuLhVE55U9pNWmf8Vkb6Am6g2cFk+sDez3/G/4OTO7L1p8+HnYgtlTWwcGA==
   dependencies:
     "@babel/runtime" "^7.7.2"
     bluebird "^3.7.1"
     fs-exists-cached "^1.0.0"
-    gatsby-page-utils "^0.0.30"
+    gatsby-page-utils "^0.0.31"
     glob "^7.1.6"
     lodash "^4.17.15"
     micromatch "^3.1.10"
@@ -6463,16 +6463,16 @@ gatsby-plugin-sass@^2.1.23:
     "@babel/runtime" "^7.7.2"
     sass-loader "^7.3.1"
 
-gatsby-plugin-sharp@^2.3.1:
-  version "2.3.1"
-  resolved "https://registry.yarnpkg.com/gatsby-plugin-sharp/-/gatsby-plugin-sharp-2.3.1.tgz#7dc85cb432d6726897dbe3a032afa433f3b5a788"
-  integrity sha512-sNfDa3GjmJUazCMYKGTn+6Vtu485sKoOkQMBhdgU7Wg8kMrrouEsFbh6313ExkbtHsslPL2RLuF+4XStxv+TBw==
+gatsby-plugin-sharp@^2.3.2:
+  version "2.3.2"
+  resolved "https://registry.yarnpkg.com/gatsby-plugin-sharp/-/gatsby-plugin-sharp-2.3.2.tgz#bf9eb6234f7a6c38a9611466f4bd7fae14635dd4"
+  integrity sha512-H+TrGwhX9vK5PY8WWNBTnsP/LtD3STmg4+XAgVTyRllmh/tVLQ1WzPCwCdoXHsnykmpUkVPLjg2rbdsKod5vwQ==
   dependencies:
     "@babel/runtime" "^7.7.2"
     async "^2.6.3"
     bluebird "^3.7.1"
     fs-extra "^8.1.0"
-    gatsby-core-utils "^1.0.19"
+    gatsby-core-utils "^1.0.20"
     got "^8.3.2"
     imagemin "^6.1.0"
     imagemin-mozjpeg "^8.0.0"
@@ -6480,6 +6480,7 @@ gatsby-plugin-sharp@^2.3.1:
     imagemin-webp "^5.1.0"
     lodash "^4.17.15"
     mini-svg-data-uri "^1.1.3"
+    p-defer "^3.0.0"
     potrace "^2.1.2"
     probe-image-size "^4.1.1"
     progress "^2.0.3"
@@ -6541,20 +6542,20 @@ gatsby-remark-external-links@0.0.4:
     unist-util-find "^1.0.1"
     unist-util-visit "^1.1.3"
 
-gatsby-remark-images@^3.1.31:
-  version "3.1.31"
-  resolved "https://registry.yarnpkg.com/gatsby-remark-images/-/gatsby-remark-images-3.1.31.tgz#8c2fe37f8d0fd1a5612de085c7d96dfae22c6cb8"
-  integrity sha512-HWCRgGejHUnQM+fClkDO28NLDplS6ag1vA5jz4HKIWJD4cs33h+Oa9W12k2kul5gJ0y5/j9xEAYDT2zdbTSS3A==
+gatsby-remark-images@^3.1.32:
+  version "3.1.32"
+  resolved "https://registry.yarnpkg.com/gatsby-remark-images/-/gatsby-remark-images-3.1.32.tgz#62ef581b1a8778949b2248e8e5c7d49e938ddeb2"
+  integrity sha512-/15LOrN0ljaWfPSRTKdGJKlfv9q/n0dFh32AHFAOnA32S2xkP1cysUu7wIV9FCG50tXny4HguIYmBp6r/ddAuA==
   dependencies:
     "@babel/runtime" "^7.7.2"
     chalk "^2.4.2"
     cheerio "^1.0.0-rc.3"
+    gatsby-core-utils "^1.0.20"
     is-relative-url "^3.0.0"
     lodash "^4.17.15"
     mdast-util-definitions "^1.2.5"
     potrace "^2.1.2"
     query-string "^6.8.3"
-    slash "^3.0.0"
     unist-util-select "^1.5.0"
     unist-util-visit-parents "^2.1.2"
 
@@ -6610,10 +6611,10 @@ gatsby-remark-smartypants@^2.1.16:
     retext-smartypants "^3.0.3"
     unist-util-visit "^1.4.1"
 
-gatsby-source-filesystem@^2.1.37:
-  version "2.1.37"
-  resolved "https://registry.yarnpkg.com/gatsby-source-filesystem/-/gatsby-source-filesystem-2.1.37.tgz#2738e3031028730952e042cf45421873c2f18d58"
-  integrity sha512-RCTgRDFwHzH+WG0aFL39TB276lnaRwrSuTlulOTBGbITA6+zaIhmpjQk/gdhl3FQUz7tw3Or+xMhcqghsoAeCA==
+gatsby-source-filesystem@^2.1.38:
+  version "2.1.38"
+  resolved "https://registry.yarnpkg.com/gatsby-source-filesystem/-/gatsby-source-filesystem-2.1.38.tgz#174fbef19826844c92e5679cb2e379eeb52acf80"
+  integrity sha512-GMsuE2lVvvKwngGSULYiLlwErU0og5TSDaSz8B/yqgqGw0EGaZc3vdcpk4PioEzHQSIR6usDCjubfmN0t3zRYw==
   dependencies:
     "@babel/runtime" "^7.7.2"
     better-queue "^3.8.10"
@@ -6621,7 +6622,7 @@ gatsby-source-filesystem@^2.1.37:
     chokidar "3.3.0"
     file-type "^12.4.0"
     fs-extra "^8.1.0"
-    gatsby-core-utils "^1.0.19"
+    gatsby-core-utils "^1.0.20"
     got "^7.1.0"
     md5-file "^3.2.3"
     mime "^2.4.4"
@@ -6631,10 +6632,10 @@ gatsby-source-filesystem@^2.1.37:
     valid-url "^1.0.9"
     xstate "^4.6.7"
 
-gatsby-telemetry@^1.1.37:
-  version "1.1.37"
-  resolved "https://registry.yarnpkg.com/gatsby-telemetry/-/gatsby-telemetry-1.1.37.tgz#bf640de90ae07c85587e70745472f0777998c468"
-  integrity sha512-krI6P4xDCI/xMV1UT+EXZ6k+8jQiBZLWuEqt3JnrocIc8Qfa7MU7YFXn012uuZzIXejw6xQo97WE7Y1gs7bZXA==
+gatsby-telemetry@^1.1.38:
+  version "1.1.38"
+  resolved "https://registry.yarnpkg.com/gatsby-telemetry/-/gatsby-telemetry-1.1.38.tgz#e8ac949565b87e37699ccbd067f55cc2fe62793e"
+  integrity sha512-uT9o5RgX2Vc4OccGCCzQeav3BstEc1Ggko5/zeov5DJxCh7eW45T9Fqd6sbZDdC78uKEPqnNeNDixcflQDWQfg==
   dependencies:
     "@babel/code-frame" "^7.5.5"
     "@babel/runtime" "^7.7.2"
@@ -6643,7 +6644,7 @@ gatsby-telemetry@^1.1.37:
     configstore "^5.0.0"
     envinfo "^7.4.0"
     fs-extra "^8.1.0"
-    gatsby-core-utils "^1.0.19"
+    gatsby-core-utils "^1.0.20"
     git-up "4.0.1"
     is-docker "2.0.0"
     lodash "^4.17.15"
@@ -6654,14 +6655,14 @@ gatsby-telemetry@^1.1.37:
     stack-utils "1.0.2"
     uuid "3.3.3"
 
-gatsby-transformer-remark@^2.6.36:
-  version "2.6.36"
-  resolved "https://registry.yarnpkg.com/gatsby-transformer-remark/-/gatsby-transformer-remark-2.6.36.tgz#619f6dd8b36b4c064ae39be7771220d8648af173"
-  integrity sha512-XhzCW5+ffV/b8ZsbZZeojtHh9OOpqnFbj1cGNMED1dCz5gv64RhStL9sX8qfo02JOuU9mu/b0wQcrxBPIfylbQ==
+gatsby-transformer-remark@^2.6.37:
+  version "2.6.37"
+  resolved "https://registry.yarnpkg.com/gatsby-transformer-remark/-/gatsby-transformer-remark-2.6.37.tgz#695202116d94a85f02a122753e8a1d22f73a12b3"
+  integrity sha512-HT1f7GcNt9YCdeKkiV1BPELU+22fErA0xjOuVVm6NVa75u1ZcZuukegRfPq4TMXb0bcCyAcSb6mJX2/GT/7qVQ==
   dependencies:
     "@babel/runtime" "^7.7.2"
     bluebird "^3.7.1"
-    gatsby-core-utils "^1.0.19"
+    gatsby-core-utils "^1.0.20"
     gray-matter "^4.0.2"
     hast-util-raw "^4.0.0"
     hast-util-to-html "^4.0.1"
@@ -6694,10 +6695,10 @@ gatsby-transformer-sharp@^2.3.5:
     semver "^5.7.1"
     sharp "^0.23.2"
 
-gatsby@^2.17.16:
-  version "2.17.16"
-  resolved "https://registry.yarnpkg.com/gatsby/-/gatsby-2.17.16.tgz#6b42b6f11f4a7fe3e58c110fbede4e18214d57eb"
-  integrity sha512-SOi7JuFlOuIS2CC0Bj3Y2zWxhr+NbcBROXNbpCTvhR8mFPOUZxOus/AnhK8Sw538AQlY0zCCUQ2QsisJikbVuw==
+gatsby@^2.18.0:
+  version "2.18.0"
+  resolved "https://registry.yarnpkg.com/gatsby/-/gatsby-2.18.0.tgz#d21e4f0f56006bff913c940e79732db4e42ea319"
+  integrity sha512-zEMd+6sJ4tkggqkAzVfJouRY5g0+MtqMOBz8tQ7bk04WIkaZJrDVyDJXcnVnmaW9y8MJmHVdHA675t4I0vZc3A==
   dependencies:
     "@babel/code-frame" "^7.5.5"
     "@babel/core" "^7.7.2"
@@ -6759,13 +6760,13 @@ gatsby@^2.17.16:
     flat "^4.1.0"
     fs-exists-cached "1.0.0"
     fs-extra "^8.1.0"
-    gatsby-cli "^2.8.11"
-    gatsby-core-utils "^1.0.19"
+    gatsby-cli "^2.8.12"
+    gatsby-core-utils "^1.0.20"
     gatsby-graphiql-explorer "^0.2.28"
     gatsby-link "^2.2.24"
-    gatsby-plugin-page-creator "^2.1.30"
+    gatsby-plugin-page-creator "^2.1.31"
     gatsby-react-router-scroll "^2.1.16"
-    gatsby-telemetry "^1.1.37"
+    gatsby-telemetry "^1.1.38"
     glob "^7.1.6"
     got "8.3.2"
     graphql "^14.5.8"
@@ -6810,7 +6811,7 @@ gatsby@^2.17.16:
     shallow-compare "^1.2.2"
     sift "^5.1.0"
     signal-exit "^3.0.2"
-    slash "^3.0.0"
+    slugify "^1.3.6"
     socket.io "^2.3.0"
     stack-trace "^0.0.10"
     string-similarity "^1.2.2"
@@ -11101,6 +11102,11 @@ p-defer@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/p-defer/-/p-defer-1.0.0.tgz#9f6eb182f6c9aa8cd743004a7d4f96b196b0fb0c"
 
+p-defer@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/p-defer/-/p-defer-3.0.0.tgz#d1dceb4ee9b2b604b1d94ffec83760175d4e6f83"
+  integrity sha512-ugZxsxmtTln604yeYd29EGrNhazN2lywetzpKhfmQjW/VJmhpDmWbiX+h0zL8V91R0UXkhb3KtPmyq9PZw3aYw==
+
 p-each-series@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/p-each-series/-/p-each-series-1.0.0.tgz#930f3d12dd1f50e7434457a22cd6f04ac6ad7f71"
@@ -14022,6 +14028,11 @@ slice-ansi@^2.1.0:
     astral-regex "^1.0.0"
     is-fullwidth-code-point "^2.0.0"
 
+slugify@^1.3.6:
+  version "1.3.6"
+  resolved "https://registry.yarnpkg.com/slugify/-/slugify-1.3.6.tgz#ba5fd6159b570fe4811d02ea9b1f4906677638c3"
+  integrity sha512-wA9XS475ZmGNlEnYYLPReSfuz/c3VQsEMoU43mi6OnKMCdbnFXd4/Yg7J0lBv8jkPolacMpOrWEaoYxuE1+hoQ==
+
 snapdragon-node@^2.0.1:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/snapdragon-node/-/snapdragon-node-2.1.1.tgz#6c175f86ff14bdb0724563e8f3c1b021a286853b"