Added ability to play archived videos (past broadcasts)

I added the ability to play past broadcasts.
The followers list will now show Live channels at the top, and all the channels you follow underneath. Selecting a channel will give you 2 options, past broadcasts and video highlights.

Twitch splits archived videos into 30 minute segments, so I just got a list of all the segments then created a playlist with them using "xbmc.PlayList()"