[BUGFIX] Fix SQL-NULL-Error with Typo3 6.2 beta4

Resolves: #55283
Releases: 6.2
Change-Id: If416b48ae4f6e212b6b5d889500b83a79eedca5a
Merge branch 'master' of git://git.typo3.org/TYPO3CMS/Extensions/realurl

Conflicts:
	class.tx_realurl_advanced.php