* removing some unused global declarations.
* removing or commenting out or adding comments for unused local vars.
* Adding one or two local var declarations.
* Declaring $matches array passed to preg_match() / preg_match_all() as array() before using [not required, just have a slight preference for the explicitness].
* remove one or two pass-by-reference function declarations where the value is not modified.
* Adding some braces to if-else blocks.
* In Parser.php, stripstrate is now an object rather than an array as per r17820, so we no longer need ask for a reference to it (as in "$x =& $this->mStripState;"), and in fact it's probably just simpler to get rid of $x altogether.
* Moving some preg regexes from "" quoting to '' quoting to stop static analyzer whinging about bad escape sequences.
... up to "LinksUpdate.php" in the includes/ directory.
Caches for wikis with table prefixes will be lost on upgrade, caches for wikis without table prefixes will be preserved. Custom cache keys in extensions can be migrated at leisure. Extensions which write to core cache keys should be migrated ASAP, as I have done with Special:Makesysop.
* Because we define the messages 'january-gen', 'february-gen', etc. as the genitive forms of months in Langauge::mMonthGenMsgs, I created them in the English file. This should fix the test of {{CURRENTMONTHNAMEGEN}} in the parser tests (currently seems to output "<january-gen>"), and should fix the wrong output of checkLanguage.php and transstat.php, which think that these messages are obsolete.
* Using the genitive forms of the months in Hebrew
* (bug 6939) Update to Indonesian localisation (id) #31
* Made lines from initialiseMessages() appear as list items during installation
* Moved the bulk of the localisation data from the Language*.php files to the Messages*.php files. Deleted most of the Languages*.php files.
* Introduced "stub global" framework to provide deferred initialisation of core modules.
* Removed placeholder values for $wgTitle and $wgArticle, these variables will now be null during the initialisation process, until they are set by index.php or another entry point.
* Added DBA cache type, for BDB-style caches.
* Removed custom date format functions, replacing them with a format string in the style of PHP's date(). Used string identifiers instead of integer identifiers, in both the language files and user preferences. Migration should be transparent in most cases.
* Simplified the initialisation API for LoadBalancer objects.
* Removed the broken altencoding feature.
* Moved default user options and toggles from Language to User. Language objects are still able to define default preference overrides and extra user toggles, via a slightly different interface.
* Don't include the date option in the parser cache rendering hash unless $wgUseDynamicDates is enabled.
* Merged LanguageUtf8 with Language. Removed LanguageUtf8.php.
* Removed inclusion of language files from the bottom of Language.php. This is now consistently done from Language::factory().
* Add the name of the executing maintenance script to the debug log. Start the profiler during maintenance scripts.
* Added "serialized" directory, for storing precompiled data in serialized form.
* Made autoloader work for unserialize()
* Made XmlFunctions.php and HttpFunctions.php autoloadable modules, via Http:: and Xml::
* Made Image class autoloadable, global functions moved to ImageFunctions.php where they can be loaded on every invocation.
* Removed some unnecessary require_once() calls
* Deferred $wgValidSkinNames initialisation
* Fixed a couple of silly construct/initialise splits. My idea from C++ experience, bad practice in PHP.
* Deferred skin initialisation in ParserOptions
* Removed $wgMwRedir during an attempt to make MagicWord autoloadable. Didn't complete that, but removing the global is still the right direction.
* remove require_once() throughout whole code, yet left in few places
* move global functions in HttpUtils, ProxyTools, Credits to class methods
* php5 only: __autoload() now used, combined with class->file map and require()
* move initialization of $wgValidSkinNames to Skin::getSkinNames()
* few more changes that will surely break stuff.