[TASK] Cleanup entry classes in typo3/ part2

Cleanup the entry classes inside typo3/ with the following
changes:

* Move language include to constructor
* Remove not needed doc-comments
* Make class available in $GLOBALS['SOBE']

Change-Id: Ie5bcf1f6f09a070a946a021d41d4809567ff6229
Resolves: #49454
Releases: 6.2
Reviewed-on: https://review.typo3.org/21669
Reviewed-by: Alexander Opitz
Reviewed-by: Markus Klein
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn
Reviewed-by: Stefan Neufeind
Tested-by: Stefan Neufeind