[CLEANUP] Let CSS Styled content use new classnames

With TYPO3 6.0, includeLibs for classes with
Namespaces / autoloader is not needed anymore.

The patch cleans up the TypoScript of CSS Styled
Content in order to use the new namings and
the superfluous call to includeLibs.

Releases: 6.2
Resolves: #55558
Change-Id: I94558a24479f220ce0fbebb54bb2f8479085c61c
Reviewed-on: https://review.typo3.org/27234
Reviewed-by: Christian Kuhn
Reviewed-by: Wouter Wolters
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring
Reviewed-by: Stefan Neufeind
Tested-by: Stefan Neufeind