Doxygen documentation update:
* Changed alls @addtogroup to @ingroup. @addtogroup adds the comment to the group description, but doesn't add the file, class, function, ... to the group like @ingroup does. See for example http://svn.wikimedia.org/doc/group__SpecialPage.html where it's impossible to see related files, classes, ... that should belong to that group.
* Added @file to file description, it seems that it should be explicitely decalred for file descriptions, otherwise doxygen will think that the comment document the first class, variabled, function, ... that is in that file.
* Removed some empty comments
* Removed some ?>
Added following groups:
* ExternalStorage
* JobQueue
* MaintenanceLanguage
One more thing: there are still a lot of warnings when generating the doc.
* Add @addtogroup tags to various classes, to try and group conceptually-related classes together.
* Add brief descriptions to various Special pages, thanks to Phil Boswell.
* Moving some docs to be right above the classes they represent, so that they are picked up.
* Convert "$dbw =& wfGetDB( DB_MASTER );" --> "$dbw = wfGetDB( DB_MASTER );"
* convert "$skin =& $wgUser->getSkin();" --> "$skin = $wgUser->getSkin();"
For the time being have not changed the function definitions of wfGetDB() or User::getSkin() [i.e. they are still both return-by-ref], so as to ensure the interface does not change for extensions [some of which may still be trying to run on PHP4 environments]. However presumably at some point this can be changed too.
Also includes tiny tweak to newlines in parserTests - will show 1 rather than 2 newlines between the "Reading tests from" strings when in quiet mode.
