Deprecate more usages of Xodx_Activity
add TODO note to PushController regarding topic uri
continue work on Notification system
add first incomplete test for xodx
forward lib-dssn-php. Fix #3
Merge pull request #5 from splattater/feauture/subscription

Fix activity stream
Update feed
write dct:references only if $attachmentUri is set
add error output when registering with a not existing person uri
Fix wrong if-null checks, add subscription to friending activity