Packages the distutils stdlib module as a standalone package,
```
377K distutils.data
221K distutils.data.br
19K distutils.js
```
to reduce the minimal pyodide size.

Part of #1542 

This also,
 - adds documentation on what's supported or not in the stdlib
 - makes a few changes to `pyodide_build/buildall.py` to be able to add such stdlib packages as a dependency in other packages (which didn't work before). For instance, until there is a release with https://github.com/pypa/packaging/pull/396 micropip has a dependency on distutils.
Unvendor distutils. Packages the distutils stdlib module as a standalone package,
```
377K distutils.data
221K distutils.data.br
19K distutils.js
```
to reduce the minimal pyodide size.

Part of #1542 

This also,
 - adds documentation on what's supported or not in the stdlib
 - makes a few changes to `pyodide_build/buildall.py` to be able to add such stdlib packages as a dependency in other packages (which didn't work before). For instance, until there is a release with https://github.com/pypa/packaging/pull/396 micropip has a dependency on distutils.
package:
  name: nose
  version: 1.3.7

source:
  url: https://pypi.io/packages/source/n/nose/nose-1.3.7.tar.gz
  sha256: f1bffef9cbc82628f6e7d7b40d7e255aefaa1adb6a1b1d26c69a8b79e6208a98

requirements:
  run:
    - setuptools

test:
  imports:
    - nose

package:
  name: nose
  version: 1.3.7

source:
  url: https://pypi.io/packages/source/n/nose/nose-1.3.7.tar.gz
  sha256: f1bffef9cbc82628f6e7d7b40d7e255aefaa1adb6a1b1d26c69a8b79e6208a98

requirements:
  run:
    - setuptools

test:
  imports:
    - nose
