Experimental recoil generation

[drobnyjt]

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Fixes #314, #302

Description

This PR swaps out the custom derived formulas for constructing an orthonormal basis for recoil generation and particle deflection with Duff et al.'s robust formula.

This also rolls in improvements to input validation and rolls-back the electronic stopping change - probably BV stopping needs two different ck for each energy regime?

Tests

cargo test passes with modification to tests.rs for the new orthonormal bases; test_cube.py reproduces the correct behavior. Other results all seem identical within statistical error.

This will break the seeded rng tests.

[drobnyjt]

Testing different branches on make_input_file_and_run.py - improved_duff refers to a branchless but otherwise identical version of the ONB algorithm. Due to the newly implemented determinism, improved_duff is identical to experimental_recoil_generation (which uses the branched version ).

The following should be done too:

• rotate_given_surface_normal in lib.rs
• rotate_back in lib.rs