Core:

Core:
* Using getUserPermissionsErrors() rather than userCan() in Title::isValidMoveOperation()
* Removing blocked check from Article::doRollback(): Title::getUserPermissionsErrors() checks for that already

API:
* Refactoring ApiMove to use new messages system
* Adding more messages to ApiBase::$messageMap
* Removing unused parameter to 'notanarticle' in ApiDelete::execute()