mixxx: Create $HOME/.mixxx if it doesn't exist.

Especially useful on newly bootstrapped systems ;-)

Signed-off-by: aszlig <aszlig@redmoonstudios.org>
mixxx: Add patch to recognize udisks path in /run.

We could enable support for creating /media/xxx, but we don't want to
because it feels kinda redundant.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>