Dysh

What's Changed
* fix issue 153 and its integration test by mpound in https://github.com/GreenBankObservatory/dysh/pull/183
* [pre-commit.ci] pre-commit autoupdate by pre-commit-ci in https://github.com/GreenBankObservatory/dysh/pull/194
* 189 review1 by teuben in https://github.com/GreenBankObservatory/dysh/pull/198
* 189 display velocity frames correctly in specplot by mpound in https://github.com/GreenBankObservatory/dysh/pull/193
* 196 selection class by mpound in https://github.com/GreenBankObservatory/dysh/pull/205

minor update to 0.2.0 because of PyPi issue.

**Full Changelog**: https://github.com/GreenBankObservatory/dysh/compare/0.1.0...0.2.0

What's Changed

Draft release candidate 3 for 0.2.0 beta

release candidate 2 for 0.2.0 beta.

This is beta release candidate 1. I still haven't done the change log yet, but we need some clean testing on this.