[BUGFIX] Disable some not finished functions in EM

The Extension Manager uses jQuery DataTables, but the
current implementation is not streamlined and causes
more trouble than it helps. Same goes for the tooltips
which are not properly styled.

As discussed with the UI/UX team we disable this
functionality and properly implement it in later
versions as bugfixes.

Fixes: #43319
Releases: 6.0

Change-Id: I432a15bce3c3933efa33f65304b01e2720b051a5
Reviewed-on: http://review.typo3.org/16770
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel