The new iconset features transparency which can be more easier generated
from svgs and looks better. For for bigger displays there are new sizes.
The bmps are the generated from the SVGs added to the tree and
create-icons-from-tango.pl is updated to enable easy generation.
rockbox-clef.svg is changed to have a bit more border.
NOTE: Icons for greyscale are unchanged. Someone needs to update them, I don't know how to do it.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@31059 a1c6a512-1295-4272-9138-f99709370657