feat: PyPI dependencies, downloading + extracting archives from PyPI

[antazoey]

What I did

Allows you to use the pypi: key for dependencies.
This key will download + extract the archive file (if one exists).
The python: key still exists; it might make sense for devs planning on publishing to pypi but haven't yet or for devs who already have or plan-to use pip to instal the dependency anyway.

How I did it

Support and handle both keys.

How to verify it

dependencies:
   - pypi: snekmate
     config_override:
       contracts_folder: src

and run

ape pm install --force

took a lookie look :

(ape) ➜  ape git:(feat/pypi) ls ~/.ape/packages/projects/snekmate/0_1_0/
CHANGELOG.md   LICENSE        MANIFEST.in    PKG-INFO       README.md      pyproject.toml setup.cfg      src

also can do:

ape pm list

Checklist

• All changes are completed
• New test cases have been added
• Documentation has been updated