[BUGFIX] Fix TYPO3 version number

Change-Id: I54a06d421bfed62b6092089d54a8afb332914323
Releases: 6.0
Reviewed-on: http://review.typo3.org/10496
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn