Inject CheckUser data more directly

To fully identify the revision specified by a recent change row we need
the data that is in rc_params.  This does not get insert into CheckUser
so I initially put the information into rc_comment.  This was less
than ideal since the comment gets reported elsewhere(rc feed, etc).

This patch adjusts so the comment is only generated for the CheckUser table
and does not get inserted to recentchanges.

Depends on I4b4a4f3855f2aaa92b5bad84a8e444cdbaf9a1af in the CheckUser
extension.

Bug: 60559
Bug: 61927
Change-Id: I5baabfebf7817f8094eca5f29dfdc776b3d3209c
Merge "Inject CheckUser data more directly"