Revert r33565 pending some cleanup...

Revert r33565 pending some cleanup...

A few notes:

* This seems to drop the 'action=success' page in favor of dumping all the output directly on the POST response. That's probably necessary, but tends to cause annoyances with back/forward navigation (warnings about re-POSTing data etc)

* The subpage checkbox is shown on the form based only on the target page's namespace. This means it'll show for the vast majority of, say, talk pages which don't have any subpages. To be consistent with the talk namespace, it should be kept hidden if there aren't any.

* Subpages may exist for a talk namespace while not existing for the article namespace. When moving an article with its talk, and the talk has archive subpages, it would probably make sense to do the moves -- but no check will show here due to the check only on the article space.

* There's a couple copy-pasted instances of $something ? ' checked="checked"' : '' ... since these are passed to a function looking for a boolean, they should just use the boolean $something. :)

* I see some unnecessary uses of =& ... this is a PHP 4-ism and not needed here.

* This query's kind of creepy:

SELECT /* MovePageForm::doSubmit WikiSysop */
page_id,page_namespace,page_title  FROM `page`  WHERE 0 = 1

* Generally speaking, there may be a _lot_ of subpages. English Wikipedia Main_Page will net you 169 total including itself, talk, and all subpages. How safe is it to move potentially thousands in one request here?