Merge pull request #55 from dvicini/master

callback activity for push
InvitionBaseFragment now starts with Invited instead of invites
Merge pull request #56 from countschokula/master

InvitionBaseFragment now starts with Invited instead of invites
fixed some major bugs in the cloud code, should now work better. Also the social db handler has now a savety net when downloading invites, cleans the server if needed