AudioMove

This version fixes an annoying usability problem:
in previous versions, the destination folder would
be automatically created if it didn't exist. That
turned out to be problematic because if the
destination referred to a mount-point which was
not currently mounted, a local directory would be
created at the mount-point's previous location.
This was very confusing for the user. In this
version, the destination widget turns pink if the
destination directory does not exist, and attempts
to write to a non-existent directory will fail,
rather than auto-creating the directory.