Music library management

I try to release a new version of bliss with new features and bug fixes each week. This week I haven't been able to because some work on the internals of bliss to support features like showing the current art size overran.

Normally each build is released to beta testers a week in advance and then promoted to a release the next week. This is why the build numbers always look like last week's date! A new version is going to beta testers today so hopefully this will be good enough to release next week.