minor bugfixes for PR https://github.com/Mastermindzh/react-cookie-consent/pull/68

- extracted code which handles setting/getting cookies.
- added correct implementation of the legacy cookie fix according to the provided url
- added cookieSecurity attribute with default value based on runtime environment
- updated README
- ran builds

build/index.d.ts

@@ -3,6 +3,8 @@ import Cookies from "js-cookie";
 
 export interface CookieConsentProps {
   location?: "top" | "bottom" | "none";
+  sameSite?: "strict" | "lax" | "none";
+  cookieSecurity?: boolean;
   style?: object;
   buttonStyle?: object;
   declineButtonStyle?: object;