[BUGFIX] Clean up the raster

Cleans up the raster of icons in docheader (row1 & row2) and tree toolbar.
Also aligned backend module headline to tree root.
List module tables also receive an standard margin to the right.

Change-Id: I96996051a3b6b4af503053d0d6b9ecb56a1be163
Fixes: #36197
Releases: 4.7, 6.0
Reviewed-on: http://review.typo3.org/10560
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe
Reviewed-by: Max Roesch
Tested-by: Max Roesch
Reviewed-by: Tolleiv Nietsch
Tested-by: Tolleiv Nietsch