users no answer rna can be used without *22

If the forward no answer extension is disabled the administrator
can still used the no answer option of the user to set a forward
on no answer to a user.
users no answer busy can be used without *23

If the forward busy extension is disabled the administrator
can still use the busy option of the user to set a forward
on busy to a user.
Merge remote-tracking branch 'origin/4928-forward' into review