[BUGFIX] Content elements disappear on publishing a page

[BUGFIX] Content elements disappear on publishing a page

The different ways of versioning (element, page, branch) have
been defined to element versioning some TYPO3 version ago. With
TYPO3 4.7, those settings, especially the handling of the field
t3ver_swapmode has been removed from t3lib_TCEmain.

This leads to a chain of problems since the value of that field
will now be "0" per default which means "page versioning".

Change-Id: Ifa4dd51a02705b29c8b91ba428b18aa976a9e1de
Fixes: #38063
Releases: 6.0, 4.7
Reviewed-on: http://review.typo3.org/12533
Reviewed-by: Oliver Hader
Tested-by: Oliver Hader