Extract ForumFactory from ForumManager

The code for creating forums in ForumManager is used by ForumSharingManager and also needed by InviteeEngine. Extract it into its own class.

mentioned in merge request !170 (merged)

Reassigned to @grote

Started branch 375-extract-forumfactory-from-forummanager

Added ~8 label

mentioned in commit aad9f514

mentioned in merge request !195 (merged)

Added ~11 and removed ~8 labels

Status changed to closed by commit aad9f514

mentioned in commit ba928875

Added ~10 and removed ~11 labels

Milestone changed to %Milestone C