[MERGE] Add mail-mode GNU Emacs mail package as a mail_client option.

[Xavier Maillard]

> >> I'll make these tweaks and merge.
>> 
>> Please do not merge this patch. 

> It's just finished merging sorry - rev 3323 in bzr.dev. Is there harm in
> leaving the code in bzr.dev? If so, I can always commit a new version
> that backs out the change. Assuming the current code is a step forward,
> it may be best to leave it there until your follow-up patch supercedes it?
> 
> Either way, if you merge from bzr.dev now, you'll get my tweaks included
> in your follow-up patch.

There is no harm but this patch is really far from being ok. 
The new patch sent in    
 http://article.gmane.org/gmane.comp.version-control.bazaar-ng.general/39578 
 thread is much better IMO (see change message for reasons).

Aaron's comments have been tackled in a followup (but the followup
 has not been received in this list yet).

I recommend to unmerge rev 3323 and wait for the followup.

Regards