* Integrate $wgDeleteRevisionsLimit in Title::getUserPermissionsErrors() (only if...

* Integrate $wgDeleteRevisionsLimit in Title::getUserPermissionsErrors() (only if doing expensive checks)
* Moved WikiPage::estimateRevisionCount() and WikiPage::isBigDeletion() to Title and marked those WikiPage methods as deprecated (only call in extensions removed in r107385)
* Show an error message when deleting a page to move another one in Special:MovePage and the deletion fails due to permissions errors (previously the form would simply show again)
* Cache the result of Title::estimateRevisionCount() since it's called two times when showing the deletion form and the user doesn't have 'bigdelete' right (one for the permissions check and the other when showing the number of revisions)