Add additional information so upstream is more discoverable

[hvaara]

The Cohere client is hosted on PyPI for example, but lacks links back to the original Github repo.

Some examples of improvements:

• Add project links to PyPI. For a good template look at https://pypi.org/project/scikit-learn/.
• Add a link back to the repo in the Contributing section of the readme. Eg. to the Issues page.

[hvaara]

I wanted to add the good first issue and help wanted labels to this bug, because I think it's a good way for somebody who wants to contribute to do it. I could also do it myself, but want to keep the issue open for this reason.