Modified inductance circuit element implemented incorrectly

[markus-chem]

The circuit element modified inductance (impedance.models.circuits.elements.La(p, f)) is stated correctly in the documentation, but implemented incorrectly in the code.

Currently it is implemented as Z = (L * 1j * omega) ** alpha. However it must be Z = L * (1j * omega) ** alpha.

[shaurya20335]

I'm a master's student at NYU Tandon School of Engineering and opened #337 to fix this. The reference values for La in test_each_element were computed with the same buggy formula, so I updated those as well, added a test that Z scales linearly with L, and changed the units of L to H sec^(a - 1) to match the documented definition.