added events tab
fixed crash when all sources were unsubscribed
added table header view, added flags in news source model
mensa list section headers
added remote refresh callback in delegate
added keywords to maps search
Merge branch 'Maps' into develop
Merge branch 'News' into develop

Conflicts:
	uni-hd/news.xcdatamodeld/news.xcdatamodel/contents
corrected maps tab
Merge branch 'Mensa' into develop
fixed crash with building without campusRegion