* Removed some backtracking regexes with an O(N^2) worst case, replaced with StringUtils::delimiterReplace(). There is a beneficial functional difference: /*/ is no longer considered to be a complete CSS comment.
* Changed the parser strip state from an array to an object. This should hopefully avoid the PHP bugs with array references. StripState uses the new ReplacementArray to do the replacements, thereby supporting FSS.
* Removed DatabaseFunctions.php from the default startup sequence. Moved wfGetDB() to GlobalFunctions.php.
* Introduced the SiteStats class, with a collection of cached site stats accessor functions.
* Removed all global functions from Parser.php, they don't belong there.
* Made LanguageConverter use the new ReplacementArray class instead of managing its own FSS objects.
* Enforce a reasonable maximum length to cover most uses while preventing some dickhead from doing a 500 thousand character expansion
* Use the first padding character only for similar reasons
* (bug 7081) More input validation and checking