switcher for Windows and remove underline in main toolbar

Removes the underline, as this looks better and also removes the UI
inconsistency. The alternative is to reduce the font size of Quick
Access which is not nice.
Also removes the underline in Windows as Quickfix breaks it


Change-Id: I5d8cc5ec07dbec68e35fec525d5a61f7ee2ee885
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>