Sped up subtitle requests

If all subtitles are cached we will no longer make a request to YSubs to get an 'empty' list of subtitles. Saves ~1000ms!
Speed up API requests!

XHR requests seem to be much, much, much faster in node-webkit than node requets. We use jQuery until things work again
Update README.md
Removed version from cachedb
Update README.md