MNT: upgrade to python3 and apply our cookiecutter

[tangkong]

Naively, I propose upgrading this project to python3 and applying our standard python cookiecutter. This would bring with it the framework for running tests in GHA and installation via pypi/conda-forge

Is there a specific reason this repo hasn't been upgraded? (some py2 specific feature? Secrets?)

Rough To-Do List:

• [ ] run pyupgrade
• [ ] apply cookiecutter
  • [ ] set up cli entrypoint
  • [ ] list dependencies
• [ ] include in pcds-conda
• [ ] set up pypi project and conda-forge feedstocks

[klauer]

This should be approached with extreme caution

Some scripts here are used to boot every single IOC in the LCLS: https://confluence.slac.stanford.edu/display/PCDS/Detailed+Soft+IOC+boot+process