Add stand-alone Python data ingest tool. (#667)

* Adding YAML file with fixed GFS data locations.

* Use "download" as protocol.

* Adding WIP script to retrieve data using yml.

Does not work at all at this point.

* Updates to allow working ingest.

* Turn on logging and clean up after htar.

* Adding support for RAP/HRRR/NAM

* WIP.

* Fixing paths, testing HRRR, error if nothing found.

* Better handling of un-found dataset via wget.

* Adding capability to copy files from disk.

* Linting.

* Addressing review concerns.