Fixed compile errors
auth: added simple AuthFilter
Switched to jersey 2

No mode codehaus jackson!
retrofit: added JacksonConverter for using jackson with retrofit
Moved most shared code to share repo
Merge branch 'master' of github.com:Maddoc42/Ferienakademie2014Server

Conflicts:
	src/main/java/de/ferienakademie/activity/Activity.java