Drops ember-radio-buttons addon and uses a plain input element instead. ember-radio-buttons doesn't seem to be maintained anymore and required jQuery. Also plain input element seems to be much easier to maintain.
Replaces ember-ajax by ember-fetch as ember-ajax is build on top of jQuery.ajax().
This reduces the bundle size by 25 KB (JavaScript) after gzip. Updating the size limit accordingly.
Therefore sha256 hash of encryption key is validated against one which is stored
on server on poll creation.
This one is transfered as X-Croodle-Proof-Key-Knowledge HTTP HEADER.
Prevents an attacker of transmitting data with wrong encryption key, which
would cause decryption errors for legit users.
