*Remove DB query: SELECT user_name FROM user. We're working with an article object, we already know the user name, use getUserText() instead of User::whoIs
This also allows us to provide *which* anonymous user it was.
*Provides first parameter to message 'anonymous': number of anonymous editors.
*Adds second parameter to message 'anonymous': IP/list of ips of the anonymous editors. Don't include $2 in the message to avoid listing the ips.
Patch against 1.13. Needs merge with r39603 (Addition of Credits::link() and use of User object will need to be undone).