Handle non-ASCII filepaths better

Use NFD normalisation form, same as filesystem #2

mpc can't handle UTF-8 paths using a different normalisation to the filesystem, presumably because it's not a native Mac app (native APIs transparently normalise filepaths).

Handle volume unavailable

Correctly handle "volume unavailable" #1

Fix build script

Include all libraries in build #1

Initial release

Control MPD from Alfred 3