bump to Gotham 13.1 beta1
[music] fix albumartist being used as a filter in song smartplaylists
Merge pull request #4680 from MartijnKaijser/13.1_b1

13.1 b1
Merge pull request #4664 from Montellese/broken_checks

fix broken comparisons
Conflicts:
	xbmc/settings/windows/GUIControlSettings.cpp
Merge branch 'Gotham' of https://github.com/xbmc/xbmc into Gotham