Convert all doc-strings to Google Style

[ns-rse]

Docstrings are currently written in Python's ReSructured Text.

An easier to read and more flexible docstring style is the Google Style docstrings style which Sphinx supports additional sections and renders with Sphinx via the napoleon Sphinx extension.

In particular including examples is very useful.

[ns-rse]

This is the only outstanding issue against CPC2 - pyclarity 0.3.0, whilst not complete I'm wondering if a release is required to align with the challenge?

[jonbarker68]

Yes, I think so. I was just waiting for the Cadenza recipes to be final. If it's OK with @groadabike I'd propose that we close any open PRs and make a release 0.3.0 on Friday.