Need for a knowledgebase explanation on how to handle pyproject.toml, PEP 517, and PEP 518

Issue:

pip now uses the pyproject.toml file by default as per PEP 517 and PEP 518. But that file seems to be a bit redundant with the conda meta.yaml file. I've had to delete this file from the downloaded tarballs to get builds working and it seems many other feedstocks do the same:

https://github.com/search?q=org%3Aconda-forge+pyproject.toml&type=code

Is the best practice to delete the file? pip has `-no-binary` and `--no-use-pep-517` (or did) but I haven't had luck with those flags combined with conda. Maybe someone else knows the best approach at dealing with pip trying to setup a build environment when it isn't needed because conda build already handles that.

Whatever the answer is, it would be good to add something to the knowledge base page about this. I can add something, but I'm not sure what should be added.

Environment (conda list):

```
$ conda list

```

Details about conda and system ( conda info ):

```
$ conda info

```