easy group invitation
Notification about Invite
Merge branch 'master' of https://github.com/IvenZ/htwplus into groupInvitation
Merge branch 'groupInvitation' of https://github.com/IvenZ/htwplus into groupInvitation
#136 invitation with request
#136 friend filter added
Merge branch 'master' of https://github.com/IvenZ/htwplus into groupInvitation
Merge branch 'groupInvitation'

Conflicts:
	app/views/Group/index.scala.html