Add a few lines to the readme/docs explaining why folks would want to mix conda and pip/pypi.

[dharhas]

The "Why" section only says this is something that is discouraged and that this package gives you a safe way to do it. It does explain the reasons why someone would want to mix the ecosystems. i.e. conda has strong guarantees around binary compatibility but pip/pypi has a long tail of packages that is an order of magnitude higher that the core scientific/data/ai packages that are in the conda ecosystem.