This makes it MUCH easier to see what sort option is currently
selected. Removed the mechanism of switching between labels when
the option is toggled, and instead put all the options into a menu.

Change-Id: I44142dc842d983d5438faeb06b67046bad235308
Reviewed-on: https://gerrit.libreoffice.org/34640Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Aleksandar Stefanović <theonewithideas@gmail.com>