ktmidi 0.6.0 release (and updates)

[atsushieno]

I just published the final release of ktmidi v0.6.0. The changes are mostly breaking changes that was discussed at #49 - it brings only annoyances and I am sorry for that, but we'd go forward with it.
Sometimes migration paths (Kotlin ReplaceWith) would work and sometimes they wouldn't.

All other relevant projects will be upgraded in accordance with this release.