[ActivityPub] Ensuring notice distribution

ActivityPubPlugin:
- Fix of accepted activity verbs to include SHARES
- Add attention profiles to delivery when announcing

Activitypub_notice:
- New local function to retrieve original URL
- Removal of unnecessary 'Atom*' attributes
- Small fix to the ensuring of actor profile

Activitypub_profile:
- New local function to fetch AP profiles from a collection

Activitypub_postman:
- Fix url passed in the announce activity

plugins/ActivityPub/lib/postman.php

@@ -283,7 +283,7 @@ class Activitypub_postman
     {
         $data = Activitypub_announce::announce_to_array(
             ActivityPubPlugin::actor_uri($this->actor),
-            $notice->getUri()
+            Activitypub_notice::getUrl($notice)
                         );
         $data = json_encode($data, JSON_UNESCAPED_SLASHES);