Streamer Changes

May as well pull in the changes so far, I've started work on trying to clean up some of the streamer code. There's plenty more work to be done, but with the upcoming work on the popcorn-streamer as much work may as well be pulled before its release, if not just to make it easier to work with.

I would suggest not merging this until 0.3.2 is released.

Testing:
- [x] Torrent via the UI
  - [x] Movie
  - [x] TV Show
- [x] Drag-on torrent
  - [x] Single video
  - [x] Multi-video (i.e. season of TV show)
- [x] Magnet
  - [x] Single video
  - [ ] Multi-video*

* Multiple video magnets weren't working before the pull request either.