[bug] No specific error message associated with Mesh2D inputs that have zero-length electronic stopping correction factor lists

[drobnyjt]

This input:

electronic_stopping_correction_factors = []

Produces the no-context error of:

Processing 10 ions...
Initializing with 4 threads...
[00:00:00][----------------------------------------][00:00:00] 0%
thread 'main' panicked at src\geometry.rs:419:26:
index out of bounds: the len is 0 but the index is 0

It should have crashed at the parsing step with an error associated with this kind of mistake.

[drobnyjt]

Fixed on dev branch.