midi support by default

[Harald Sitter]

https://bugs.edge.launchpad.net/ubuntu/+source/kubuntu-meta/+bug/424919

Currently kubuntu can't play midi files out of the box. This is mostly
because xine does not have a midi decoder, so any solution would
probably require either pulling in a new media backend (gstreamer?) or
using a solution that implements its own decoder (security concerns?).
Due to the lack of support in upstream xine and the limited usecase I
would reject this wish and redirect the reporter to xine. If xine
implements a decoder, kaffeine and amarok will be able to play midi.