Invalid links to Climate Data Store

[pos-ki]

At various places throughout the codebase (in README.md, CONTRIBUTING.md, and possibly more), and in the documentation, the link to https://cds.climate.copernicus.eu/api-how-to is no longer valid. I believe the current correct link is https://cds.climate.copernicus.eu/how-to-api.

The "ECMWF ERA5" link on the main website is also no longer valid.

It seems that the website has been overhauled at the end of September.

[abc8747]

Thanks for the report, we are currently rewriting the codebase (#62) and will update it to the latest CDS API. We will consider adding the Google Cloud ARCO ERA5 dataset as well.

[abc8747]

Unfortunately, the CDS API has been rather unreliable with slow download speeds. We have added new experimental code to download ERA5 using google cloud instead: https://github.com/HKUST-OCTAD-LAB/AirTrafficSim/blob/f0256ec7e2b84e75fe8a4d01294fabcdc186e1c7/airtrafficsim/experimental/performance/era5.py

The documentation containing the fixes will soon be built.