urlencoding fix, data protocol, changed cookie

Urlencoding fix: links are urldecoded when followed, but config data (cookies) shouldn't be decoded this way.

Data protocol: migrated to "data:text/html, la-la-la" from "javascript: document.write('la-la-la')".

Changed authentication cookie: "CAUTH" -> "session" (discovered by experiment).

Config format slightly modified.