Bumped development version to v0.4.1.
Bumped development version to v0.4.1.

It's debatable whether or not switching out the FSEvents backend is
really a patch update, but it's technically not working in various edge
cases in v0.4.0, and fails silently, so I don't think we have a choice
but to classify this as a bug.

havoc-io/mutagen,havoc-io/mutagen