Remove Basemap support

[adybbroe]

Code Sample, a minimal, complete, and verifiable piece of code

# Your code here

Problem description

Right now we support both Basemap and Cartopy for plotting/drawing swaths and area boundaries on a map. The former was what was the only option in the past Then Basemap was not actively supported and Cartopy had to be introduced. Cartopy seem the viable one to keep using and it serves the purpose just fine. The code would be easier to read and maintain if we removed the Basemap support.

Expected Output

Actual Result, Traceback if applicable

Versions of Python, package at hand and relevant dependencies

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