Tuatara

Mostly minor bugfixes.

What's Changed
* Update pillow for CVE
* Add opus to file types, allow mixed case filenames
* Don't go down fetching art if either of artist or album are missing

**Full Changelog**: https://github.com/wenottingham/tuatara/compare/v0.3.1...v0.3.2

Minor display tweaks.

Window title is now artist + title.
Program title and version is now in help screen.

Feature/bugfix: proper exception handling & termination
Bugfix: handle files that GStreamer needs escaped
Bugfix: better multidisc searching in MusicBrainz

Refactor visualization so it's more seamless, at the expense of CPU usage. Also work around a bug with seeking + visualization.

New features:
- Visualization support (via gstreamer visualization plugins)
- Cover art fetching now done asynchronously

First release of tuatara.

Can be installed from sdist, wheel, or you can download the tuatara "binary" for your appropriate python version.