Properly integrate $wgAbuseFilterValidGroups

The concept of different AbuseFilter groups had not properly been integrated, but should be now:
- The total number of matches is now group-specific
- .. Which will also fix the emergency shutdown calculations
- And a portion of incorrect code (involving $logged_local_filters) has been fixed (action != group)

Change-Id: I091199a9d74aee47dcb3d8942394a28e0ffd3234
Merge "Properly integrate $wgAbuseFilterValidGroups"