Upset-alttxt

Implements various feedback on alttxt generations, plus new command-line params.

Allows generating of alt texts from JSON state+data downloads from the Multinet app. Fully implemented, mostly stable. README is up-to-date, code works, but the tests have not been updated and will not be for some time.

What's Changed
* Fix a fatal bug resulting from a division by zero error when empty intersections are included in the state.

**Full Changelog**: https://github.com/visdesignlab/upset-alt-txt-gen/compare/v0.5.1...v0.5.2

What's Changed
* Add support for set queries by NateLanza in https://github.com/visdesignlab/upset-alt-txt-gen/pull/81


**Full Changelog**: https://github.com/visdesignlab/upset-alt-txt-gen/compare/v0.5.0...v0.5.1

What's Changed
* Enhance glossary formatting in markdown output by bolding terms by JakeWags in https://github.com/visdesignlab/upset-alt-txt-gen/pull/79


**Full Changelog**: https://github.com/visdesignlab/upset-alt-txt-gen/compare/v0.4.9...v0.5.0

**Full Changelog**: https://github.com/visdesignlab/upset-alt-txt-gen/compare/v0.4.8...v0.4.9