Use strings as values for enum instead of integers

[ecomodeller]

Inspiration from From stringly typed to strongly typed: Insights from re-designing a library

[ecomodeller]

Turns out you can use strings as the backing values for enums, which makes it trivial to construct given the correct string.

Question is do we still need/want to support the more flexible version?

modelskill/modelskill/types.py

Line 22 in 36cc9a2

def from_string(s: str) -> "GeometryType":

[ecomodeller]

Static type checks fails, we need to merge #470 first.

[jsmariegaard]

Love it!