This task just changes one line of css to remove the senseless space
between a panel and it's related tbar.

This is useful, because the space between toolbar and panel was bigger,
than the space to neighboor panels.

Change-Id: I631acb14d1ed598f2e5718b84b21d76277a37391
Resolves: #28793
Releases: 4.6
Reviewed-on: http://review.typo3.org/4170
Reviewed-by: Stefan Neufeind
Reviewed-by: Fabien Udriot
Reviewed-by: Xavier Perseguers
Tested-by: Xavier Perseguers