Metriculous

* New look for confusion matrix
* `Comparison.save_html` automatically generates a file name unless a path is specified
* Improved figure sizing when there is only a single model in a comparison
* Various performance improvements
* Fix for a crash in `compare_classifiers` when some of the classes are never predicted

* Fixed an issue that had caused one-vs-rest classification figures (such as ROC curves and PR curves) to be displayed
only for the last class.
* Fixed a minor issue that had led to non-centered output in some versions of Jupyter lab / notebook.

* This release makes everything much better.

* Initial release.