updated news model (removed color attribute from UHDNewsSource, added thumbIconData), display icon in NewsSourceCell
updated VIOSFramework
Merge branch 'Mensa' into develop
Merge branch 'Mensa' of https://github.com/Uni-Heidelberg/Uni-HD-App into Mensa
Merge branch 'News' of https://github.com/Uni-Heidelberg/Uni-HD-App into News

Conflicts:
	uni-hd/news.xcdatamodeld/news.xcdatamodel/contents