[BUGFIX] FILES ContentObject ignores language handling

The FILES TypoScript ContentObject, which is responsible
for rendering content element type "uploads" does not take
care of languages and pages_language_overlay table.

Change-Id: Ic311cf2162253bb1a382985df63999142b780555
Releases: 6.0
Resolves: #42357
Reviewed-on: http://review.typo3.org/16098
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel