Fix for 'Create' page dropdown not always updating when selecting a new page in the SiteTree

This was only updated when the 'Create' page options was open, so if you selected a different page and then clicked the 'Create' button it would have the original options
Fix to pass Travis for 2.4 version of SS
Replaced ereg_replace with preg_replace as ereg is deprecated
Merge branch 'post-2.4' of github.com:oilee80/silverstripe-cms into post-2.4

Conflicts:
	code/CMSSiteTreeFilter.php