…ebookresearch#126)

Summary:
See title.
Links to run on colab:
201: https://colab.research.google.com/github/facebookresearch/Kats/blob/master/tutorials/kats_201_forecasting.ipynb
203: https://colab.research.google.com/github/facebookresearch/Kats/blob/master/tutorials/kats_203_tsfeatures.ipynb
204: https://colab.research.google.com/github/facebookresearch/Kats/blob/master/tutorials/kats_204_metalearning.ipynb

## Kats

Thank you for contributing! Please take a moment to review our [**contributing guidelines**](https://github.com/facebookresearch/Kats/blob/master/CONTRIBUTING.md)
to make the process easy and effective for everyone involved.

- [ ] Fork the repo and create your branch from master.
- [ ] If you've added code that should be tested, add tests.
- [ ] If you've changed APIs, update the documentation.
- [ ] Ensure the test suite passes.
- [ ] Make sure your code lints.
- [ ] If you haven't already, complete the Contributor License Agreement ("CLA").

Contributor License Agreement ("CLA")
In order to accept your pull request, we need you to submit a CLA. You only need to do this once to work on any of Facebook's open source projects.

Complete your CLA here: https://code.facebook.com/cla

`Ver: Kats v1.02`

Pull Request resolved: facebookresearch#126

Test Plan: Notebooks run successfully locally in jupyter and on colab

Reviewed By: jeffhandl

Differential Revision: D30860476

Pulled By: rohanfb

fbshipit-source-id: 9c04a1402414b75ca48600c5d26002c42ff4ed1d