Update documentation and code to run c302/c302_*.py as python -m c302.c302_*

[mwatts15]

Relative imports break in possibly unexpected ways when you run a script from inside of its package directory rather than let python do it for you with -m

[pgleeson]

Thanks for testing and opening the issues @mwatts15.

Will look to tidy up/document this repo more, test out the latest PyOpenWorm and address these issues.

[jaideep-seth]

I would really like to test and document the latest in PyOpenWorm, could you guide me on how i can help here? @mwatts15