Show who deleted a comment and when (for people who can see deleted comments)

[cellio]

Moderators and admins can see deleted comments, but can't see who deleted them or when they were deleted. It would be helpful to know if a comment was self-deleted (the user realized the problem and corrected it) or deleted by a moderator/admin. In the latter case, it would be helpful to know if it was deleted by someone involved in the discussion; we sometimes get complaints about conflicts of interest. The timestamp of the deletion can help in reconstructing a sequence of events if there's a dispute between users.

For communities with multiple moderators (which we hope will be all of them in time), this information would help mods coordinate ("oh, since you're already familiar with that, could you look at...?" and the like).