INTEG-274: [integ-forum] No information update of Forum activity after moving replies

Fix description:
- Problem: Not yet implement action move post for activity stream
- How to fix? : Implement function movePost for activity stream:
-- Add new comment for moved postes on activity stream of destination topic
-- Delete comment for moved postes on activity stream of source topic
Merge commit '6e62d0f00f8e91e507208e20cf93d0f3c4505f87' into HEAD