streamer.js changes - initial buffering, refactoring, jshint

Commit 527e7db28abd5264fc8966f86c42b268321cf00b introduced resumable movies/TV shows, however initial buffering would require a specific amount of the torrent to be downloaded before playing. If the user's already downloaded the entire thing, it'll refuse to play. So we switch to the number of verified pieces the client has as a better estimate of what they already have.

Fixed a couple of syntax hiccups that jshint whines about too.