Trakt collection deletion

I have added a way for Sick Beard to notify Trakt that an episode that has been rescanned and ignored is no longer in the collection. To do so I have updated the updateLibrary() function in trakt.py to include a boolean argument to allow for deletions.

PS. This is a rewrite of pull request 289 (https://github.com/midgetspy/Sick-Beard/pull/289), which messed up the other branches since I modified stuff in the master branch.