Add pyproject.toml

[freemansw1]

Resolves #442 and adds a (fairly basic) pyproject.toml to tobac.

Note that this is proposed as a merge to main.

• Have you followed our guidelines in CONTRIBUTING.md?
• Have you self-reviewed your code and corrected any misspellings?
• Have you written documentation that is easy to understand?
• Have you written descriptive commit messages?
• Have you added NumPy docstrings for newly added functions?
• Have you formatted your code using black?
• If you have introduced a new functionality, have you added adequate unit tests?
• Have all tests passed in your local clone?
• If you have introduced a new functionality, have you added an example notebook?
• Have you kept your pull request small and limited so that it is easy to review?
• Have the newest changes from this branch been merged?

[freemansw1]

The failing CI will be resolved after #465 is merged; we will wait to review/merge until that is merged.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 60.67%. Comparing base (706b3ee) to head (e993b4f).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #464   +/-   ##
=======================================
  Coverage   60.67%   60.67%           
=======================================
  Files          23       23           
  Lines        3537     3537           
=======================================
  Hits         2146     2146           
  Misses       1391     1391           

Flag	Coverage Δ
unittests	60.67% <ø> (ø)

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[w-k-jones]

Great, thanks for adding this! Happy for this to be merged

[w-k-jones]

Is there a way to get the version from the __init__.py file as previously?