[MERGE] Added support for a hook before sending the commit message to the editor.

[John Arbash Meinel]

Alexander Belchenko wrote:
> Alexander Belchenko has voted comment.
> Status is now: Waiting
> Comment:
> why for it's needed?

I believe his idea is to be able to have a plugin set a default commit 
message based on what files have been modified, etc. It could also check 
to see if there is a merge, and set up a default message from that.

I think it could be pretty useful.

John
=:->