Old t3lib_tcemain was renamed to Core\DataHandler\DataHandling, but
should have been Core\DataHandling\DataHandler instead, located
beside the other classes and hook interfaces.
The patch moves the file and corrects all usages, and raises
submodule pointers of workspace and version that already got
the rename patches.

Change-Id: I394849aceebc389d88b0da0f0ff9751a7cc8efc5
Resolves: #41094
Related: #40095
Related: #41095
Related: #41096
Releases: 6.0
Reviewed-on: http://review.typo3.org/14762
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn