[BUGFIX] RealUrl: Fixing fatal error in info module in TYPO3 6.2

RealUrls Info -> RealUrl Management module throws an fatal error because
of an class it cannot find. This patch adds the class to the
ext_autoload.php and fixes this error.

Resolves: #51471
Releases: 6.2
Change-Id: I94f3a3e588a4ccf0ec02c42f0b73948ac877de77
Reviewed-on: https://review.typo3.org/23430
Reviewed-by: Stefan Fürst
Tested-by: Stefan Fürst
Reviewed-by: Kai Ole Hartwig
Tested-by: Kai Ole Hartwig
Reviewed-by: Dmitry Dulepov
Tested-by: Dmitry Dulepov
Follow up for #51471