Pacifica-downloader

Changed
- Fix 24 Add kwargs to Downloader by [dmlb2000](https://github.com/dmlb2000)
- Pull 29 Remove Requirements Pip>=20 by [dmlb2000](https://github.com/dmlb2000)

Added
- Pull 22 Add Python 3.7 and 3.8 by [dmlb2000](https://github.com/dmlb2000)
- Pull 21 Add Ansible to Travis CI by [dmlb2000](https://github.com/dmlb2000)
- Fix 17 Add Extra Args to CartAPI by [dmlb2000](https://github.com/dmlb2000)
- Pull 19 Update Pylint 2.0+ by [dmlb2000](https://github.com/dmlb2000)
- Pull 18 Remove Python 2.7 Support [dmlb2000](https://github.com/dmlb2000)

Added
- Download classes to interface with Cartd API
- Method classes for parsing metadata
- CloudEvent notifications
- Policy API transaction

Changed