show depends on matplotx

[GitHimanshuc]

import orthopy

orthopy.c1.jacobi.show(5, "normal", 0.0, 0.0)

gives, ModuleNotFoundError: No module named 'matplotx'

matplotx is not installed by default when installing orthopy.

[nschloe]

It's an optional dependency. You can install orthopy with

pip install orthopy[all]

to get them all.

[nschloe]

I'll just make the dependencies mandatory until someone complains. :)