[Mediawiki-api] New API features and changes

[Yuri Astrakhan]

New Features:
* list=search:  Full text search has been added - both titles and
content are now search-able.
* list=allusers: Added groups - can be both filtered by a specific
group, and shown the groups the users belong to. (bug 10684 by
VasilievVV)

Breaking change:
* prop=revisions: I removed the redundant pageid= attribute in the
<rev> tag - pageid is already given as part of the parent <page>
element. (Thx Platonides)

Your help is still needed to improve documentation at
http://www.mediawiki.org/wiki/API - each function and parameter needs
better documentation, with many simple examples. There is a template
to help with the presentation.

As usual, if you notice any bugs -- http://bugzilla.wikimedia.org
Awaiting server sync for changes to go live.

--Yurik