[p4] Preventing Merging into a branch

[Robert Cowham]

> Is it possible to somehow only permit merging into one branch 
> from a specified branch? We want to restrict merges into 
> "Stable" so that they only come from "Main". 

Yes via a pre-submit trigger. You would run the "p4 resolved" to see where
the files came from and reject as appropriate.

> Also Is it somehow possible to to ensure that a specific 
> attribute is set on all the files involved in a merge onto 
> stable before permitting the merge to go ahead? We want to 
> ensure that the "Peer Reviewed"
> attribute is set before moving onto the "Stable" branch.

Yes also via a trigger. 

Robert