NASA CMR

We (@scottyhq, @apawloski, and others) are interested in building a Intake interface to NASA's CMR. NASA is currently in the early stages of moving its data storage to public cloud (mostly AWS). As part of a NASA funded project, we are interested in building a intake meta-catalog of collections based on CMR.

> NASA's "Common Metadata Repository (CMR) is a high-performance, high-quality, continuously evolving metadata system that catalogs all data and service metadata records for the [Earth Observing System Data and Information Systems (EOSDIS)] system and [is] the authoritative management system for all EOSDIS metadata."

References:
- CMR: https://earthdata.nasa.gov/about/science-system-description/eosdis-components/common-metadata-repository
- Python APIs: https://pypi.org/project/python-cmr/, https://github.com/nasa/pyCMR
- NASA EOSDIS cloud: https://earthdata.nasa.gov/about/eosdis-cloud-evolution

In talking with @martindurant, it sounds like we can probably write a custom Data Source wrapper around CMR. I'm hoping to connect Martin and Andrew here in this issue.