Merge maintenance-work branch:

Merge maintenance-work branch:
* (bug 16322) Allow maint scripts to accept DB user/pass over input or params if no AdminSettings.php
* (bug 18768) Remove AdminSettings.php from MediaWiki core
* (bug 19157) createAndPromote error on bad password
* (bug 14201) Create AdminSettings.php during wiki installation, in the same way as LocalSettings.php
* Introduce new Maintenance class framework and port a good number of scripts over; the ones that are left are a little more complicated. Read the docs.
* Not deleting "unused" files yet, don't want to break everything at once :)