Remove use and dependencies on QTKit now that we are using AVFoundation for media playback.
<rdar://problem/14265204>
Created attachment 226532 [details] Patch
Locally, after this patch, I see two failures that seem to be due to color space on my development system. Watching EWS to see how things fare on a valid test system.
While this change works, we want to keep QTKit support on the Mac for the time being.