Post-processing: Make python library installable with pip

[Ed Hone (EdHone)]

Description

Makes the post-processing tools installable with pip. Some repo restructuring was needed to make CLI tools discoverable by setuptools.

To test, try installing package with pip inside a venv:

python -m venv test_vernier_install
source ./test_vernier_install/bin/activate
pip install post-processing/

and try running the unit tests and CLI:

python -m unittest discover post-processing
summarise-vernier post-processing/vernier/tools/vernier-output-example-collated

Linked issues

Closes #233

Type of change

• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How has this been tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• New tests have been added
• Tests have been modified to accommodate this change

Checklist:

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes, for both debug and optimised builds

[Oakley Brunt (oakleybrunt)]

Looks good to me :D

[Sam Clarke-Green (t00sa)]

Copying my reply here for posterity: it all looks good to me. I suspect the easiest way to manage the installation with spack might be to continue with the existing core vernier package and to introduce a new py-vernier-tools package to install the user-facing commands.