Making CLASSICS packageable

[mtryan83]

Hi,
I'm working through making some of my scripts/notebooks/etc. python packages (possibly for eventual PyPI and/or conda and/or other release) and I'd like to use this repo as a dependency. As such there would need to be either a setup.py or pyproject.toml file (preferred) so that it can be installed directly from the repo. Would you be willing to add one? The one I've been using in my personal copy is

[build-system]
requires = ["setuptools>=61.0"]
build-backend = "setuptools.build_meta"

[project]
name = "CLASSICS"
version = "0.0.1"
authors = [
  { name="Brian Colquhoun", email="bcolqu@yorku.ca" },
  { name="Saniya Heeba", email="heeba@physik.rwth-aachen.de" },
  { name="Felix Kahlhoefer", email="kahlhoefer@physik.rwth-aachen.de" },
  { name="Laura Sagunski", email="sagunski@itp.uni-frankfurt.de" },
  { name="Sean Tulin", email="stulin@yorku.ca" },
]
description = "CalcuLAtionS of Self Interaction Cross Sections"
readme = "README.md"
requires-python = ">=3.8"
license = {file = "LICENSE"}
classifiers = [
    "Programming Language :: Python :: 3",
    "License :: OSI Approved :: BSD-3",
    "Operating System :: OS Independent",
]
dependencies = [
    "numpy",
    "scipy",
]

[project.urls]
Homepage = "https://github.com/kahlhoefer/CLASSICS"
Issues = "https://github.com/kahlhoefer/CLASSICS/issues"

But I don't know how accurate/up-to-date this is. I'm also happy to make this into a pull request, if that's easier.