Fix H.264 level preference with universal transcoder.
Merge pull request #258 from ljunkie/master-roku-hud-releasedate

Add Release Date + Transcoded/Direct Play to the Roku HUD (down arrow)
Remove X-Plex-Account header. We hardly knew ye.
Delete some unused functions.
Add transcode session info to the HUD, fixes #259.
Fix a crash in Playback Options for non-PMS content.
Ask the transcoding server about the session, not myPlex.
Add the container format to the HUD when direct playing.
Add Now TV to known models.
Move some prefs under the new-ish Audio Prefs screen. h/t @ljunkie

It's kind of a tossup, since the prefs *are* advanced. But now that we
have an audio prefs screen anyway, it makes sense for these to live
there.
Add a toggle for DTS support, fixes #267.
Only use the universal transcoder with items that have streams.
Make sure we have video details before trying to play, fixes #265.
Don't Direct Play when first stream is unsupported surround sound.

It's too likely that the stereo stream coming after the surround sound
stream is commentary. And we can't always trust the Roku to choose the
right stream anyway.
Update Makefile and README for recent changes.

My Roku is now requiring authentication on installer requests.
Bump version to 2.6.8 and add release notes.
Fix crash in adding server manually.
Fix titleseason watched status
Merge pull request #272 from ljunkie/master-fix-tv-scrobble-titleseason

Fix titleseason watched status. Fixes #270.
Update supported H.264 level to 4.1. Fixes #269.