[FEATURE] Add ExtJS xtype:modulepanel for BE Modules

This is a follow up change to #12664.
It adds a new Extjs xtype called modulepanel and the required styles.

This way we can have extjs modules which fit the TYPO3 look'n'feel.

The CSS modifies the tbar and the bbar to look like the standard
toolbars in TYPO3.

4.5 is added to releases, as #12644 is the direct parent.

Change-Id: I596962fc81e66368db06059447b2f6a09db4ff73
Resolves: #28384
Releases: 4.6, 4.5
Reviewed-on: http://review.typo3.org/3696
Reviewed-by: Georg Ringer
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe
Reviewed-by: Steffen Kamper
Tested-by: Steffen Kamper