feat: added first typescript support

Didn't add many types yet. Just used to test out typescript compiler, copying files and building.
Now that all that seems to go well I can start converting all files to .ts and then adding proper typing everywhere

.eslintrc

@@ -0,0 +1,12 @@
+{
+  "root": true,
+  "parser": "@typescript-eslint/parser",
+  "plugins": [
+    "@typescript-eslint"
+  ],
+  "extends": [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/eslint-recommended",
+    "plugin:@typescript-eslint/recommended"
+  ]
+}