CHANGELOG:
**Improvements**
- Improved testing for DataStore class (thanks to JohanRodhe for contribution)
- Improved default color palettes (inspired by Scanpy)
- Improve legends display for `plot_layout`. Cleaned up code in `plots.plot_scatter` and all affected `DataStore` wrappers.
**Known issues**
- Tests fail on MacOS
- Unable to reproduce results of Leiden and UMAP on Github actions. Can reproduce locally
**Other changes**
- Minimized README for Github repo
- Improved logo layout for Github README
- Improved logo formats for Github and RTD
- Using Github actions for testing now. Not using CircleCI anymore. This was motivated by difficulty of changing testing OS.