Fix for invalid torrent files causing NoneType errors.
Further corrections for torrent download issues related to content being empty and not properly checked in advance.
Fixed issue with reverts to master on startup due to bug in version checker.

Fixed issues with indexerApi caching code, seemed TVRage was really the only one experiancing the problems but has been corrected for theTVDB just in case.
Merge remote-tracking branch 'origin/nightly' into nightly