Feedx

Use matplotlib for plotting and migrate plotting function from colab notebooks into the package.

**Full Changelog**: https://github.com/google-marketing-solutions/feedx/compare/0.0.2...0.1.0

* Added the ability to skip the data validation checks.

**Full Changelog**: https://github.com/google-marketing-solutions/feedx/compare/0.0.1...0.0.2

First version of FeedX, with the functionality to design and analyse both regular and crossover experiments.