Large update to the frontend to make use of the websocket API instead of
the REST-based API.  I think there may be some downsides to doing things
this way, but there should be a lot of upsides, too:

* Upload progress now works properly (though I introduced a non-standard
  method to the websocket to allow this)
* Requests should be quicker in general since we already have the
  connection open
* I'm more likely to update the websocket API, since upstream has
  decided on a websocket-based API

Everything seems to be working well so far.  Game list with
upload/download/boot/trash, status page, and memory viewer are all
working.  Patches not going through websocket yet, and still need to
update ZeldaHUD and SMW cheats.