GitLab

Moved most of the heavy-lifting for account restoration out of
restoreuser.php and into its own class, with the hope that we'll do
the work from the Web eventually.

Cleaner code to avoid a couple PHP notices from accessing uninitialized variables in ostatus profile discovery (these cases hit checking diaspora accounts)

Mark OembedAction, XrdAction, and (plugin) AutocompleteAction as read-only. Tweaked ApiStatusesShow and ApiTimelineUser to still claim read-only when hit with a HEAD request (usually link checkers or a precursor to a GET, and should be semantically equivalent to a GET without actually transferring data)

Router entry for AtomPubService was slightly off, generating an incorrect link in the RSD data.

AtomPub test cases: make sure the posted entry appears in the feed, and that it disappears after deletion

AtomPub fix: correct the response URL given from posting a new message (wrong parameter meant we got the main page instead of the message's URL)

The new DeleteaccountAction lets a user delete their own account
(subject to global rights set by the admin). It presents a form to
delete the account, with an "I am sure." text entry box.

It then schedules the account for deletion and logs the user out.

TwitterBridge: partial merge of id_str usage from 0.9.x for improved 32-bit and pre-5.2.10 compatibility. (on 64-bit in 5.2.6 we can pull the integer IDs, but silently lose some precision on the end.)

Fixes for Twitter bridge breakage on 32-bit servers. New "Snowflake" 64-bit IDs have become too big to fit in the integer portion of double-precision floats, so to reliably use these IDs we need to pull the new string form now.
Machines with 64-bit PHP installation should have had no problems (except on Windows, where integers are still 32 bits)

Conflicts:

	plugins/TwitterBridge/twitterimport.php <- as this hasn't been broken out, the import code is NOT FULLY UPDATED HERE.

Feed for group memberships, in activity streams format.

Shows a feed; has proper pagination; accepts activitystreams "join"
activities to start a new membership.