Change logging command to help debug Moto issue (#2165649)

* It has been reported that messages for a particular user are not
  staying in sync re: deletions via PC
* This hasn't been reported elsewhere
* The new logging command logs the subject of deleted messages which
  will help track down the problem
* I have also requested, and expect to receive, an account on the
  Moto server in question to try to replicate the issue

Requesting Dr. No approval for this important change to user logging
code.

Change-Id: I13229d843ef828b54f3514bdded5a7561a87989a
1 file changed