0.3 pre-release

[betolink]

This is the firs release that will make earthdata actually usable. The main changes are in the auth class but also using the NASA fork for CMR so now we can query for other things and not just datasets and granules but also variables, missions and more!! the cost of this update is that we no longer support Python 3.7.

Auth:

• we can now use auth.refresh_tokens() to force token updates from CMR
• with .login(strategy="interactive", persit=True) we can create or append a .netrc file with the user's credentials.
• using tinynetrc instead of default netrc library

Documentation:

• documentation is generated for github pages and readthedocs
• Full Jupyter notebooks are in place and can get executed and rendered to the documentation, for now set to False
• Classes and their methods are documented in the user reference section, following the amazing style of QGreenland documentation

Granules

• the data_links() method now accepts access as param with on_prem or direct as values to get the links the user is looking for. direct means S3:// links if the dataset is cloud based.