miro: New package, version 6.0.

I actually had this breeding in my nixpkgs overrides for a year and only
recently took the time to fix it and thus revive my video feeds :-)

The package uses a patch which is removing the dependency on gconf and
switches to storage within a shelve in ~/.miro/config instead.

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