* Write array literals with one item per line. This makes diffs which add or remove items far easier to interpret, and makes merging such changes feasible. And it looks nicer too.
* Use line breaks to show the logical structure of your code. This enhances readability. Bring similar elements in a list into alignment, in order to reveal the differences between those elements at a glance.
* Removed a fun game of spot-the-difference in AbuseFilterHistoryPager::getQueryInfo(). If I want fun games I'll play UFO:AI.
* Moved some oddly placed assignments (in expressions) to their own statements: such assignments reduce readbility.
* Add searching and filtering functionality to the existing 'test' interface.
* Add an 'examine' interface designed for testing filters against a previous change, selectable through the search interface in either the 'test' or the 'examine' view.
* Minor enabling change in ChangesList core, to allow subclassing.
