Mitoviz

------------------

* Refactor to use abstract classes;
* Rename internal classes to _PolarLocus and _PolarVariant.

==================

* Add ``plot_table`` function to plot variants from tabular files;
* add CLI functionality to plot variants from tabular files;
* refactor code.

==================

* Add ``plot_df`` function to plot variants from a pandas DataFrame.

------------------

* Make legend plotting optional.

------------------

* Add option to plot variant labels.

------------------

* Add legend to plots and update colors.