Gamma ray propagation

[andrewfullard]

Description

This cleans up the previous PR and consists of:

• Montecarlo code to propagate decay products in ejecta (photons only)
• Handling of immediate positron decay
• Some unit tests
• A little documentation

Motivation and context

This code is the first step in late-phase SNe Ia simulations in TARDIS

How has this been tested?

• Testing pipeline.
• Other.

Examples

Notebook included in PR
Type of change

• Bug fix.
• New feature.
• Breaking change.
• None of the above.

Checklist

• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
  • (optional) I have built the documentation on my fork following the instructions.
• I have assigned and requested two reviewers for this pull request.

[Rodot-]

Looks good to me, I'll approve once black passes

[codecov]

Codecov Report

Merging #1698 (992fe6f) into master (0205add) will decrease coverage by 1.79%.
The diff coverage is 28.85%.

❗ Current head 992fe6f differs from pull request most recent head ee905cb. Consider uploading reports for the commit ee905cb to get more accurate results

@@            Coverage Diff             @@
##           master    #1698      +/-   ##
==========================================
- Coverage   60.13%   58.34%   -1.80%     
==========================================
  Files          70       76       +6     
  Lines        8108     8599     +491     
==========================================
+ Hits         4876     5017     +141     
- Misses       3232     3582     +350     

Impacted Files	Coverage Δ
...dis/montecarlo/montecarlo_numba/formal_integral.py	53.87% <ø> (ø)
tardis/plasma/properties/atomic.py	55.73% <0.00%> (-0.45%)	⬇️
tardis/plasma/properties/continuum_processes.py	35.75% <0.00%> (ø)
tardis/montecarlo/montecarlo_numba/base.py	29.75% <7.14%> (-2.07%)	⬇️
...dis/montecarlo/montecarlo_numba/numba_interface.py	34.90% <15.38%> (-1.32%)	⬇️
tardis/energy_input/gamma_ray_grid.py	19.60% <19.60%> (ø)
tardis/energy_input/gamma_ray_interactions.py	20.40% <20.40%> (ø)
tardis/energy_input/energy_source.py	27.63% <27.63%> (ø)
tardis/io/atom_data/base.py	81.81% <28.00%> (-7.90%)	⬇️
tardis/energy_input/util.py	32.30% <32.30%> (ø)
... and 3 more

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[andrewfullard]

Some of the docstring failures are confusing. It claims 7 functions in e.g. calculate_opacity.py but there is definitely only 6.