Package name and `.tar.gz` names should be consistent

[michalrus]

E.g. websocket-client’s file name is websocket_client which breaks tools like Nixpkgs’ fetchPypi, c.f. https://github.com/NixOS/nixpkgs/blob/56a605c8b9bce331bd562778b8f56cd957a8c90f/pkgs/top-level/python-packages.nix#L72-L88.

A discussion from freenode/#pypa:

21:42 <michalrus> Hello, can you tell my why this URL returns 404? https://files.pythonhosted.org/packages/source/w/websocket-client/websocket-client-0.52.0.tar.gz

21:42 <michalrus> While it should redirect to https://files.pythonhosted.org/packages/30/c8/82ac8ae45073034af51c6296c35346caab4fa26456c19f9cf64d2b978971/websocket_client-0.52.0.tar.gz

21:42 <michalrus> … as happens for any other package.

21:46 <di_codes> michalrus: the package name is sensitive to the format used when uploading, it's websocket_client-0.52.0, not websocket-client-0.52.0: https://files.pythonhosted.org/packages/source/w/websocket-client/websocket_client-0.52.0.tar.gz

[…]

21:52 <di_codes> we probably should be normalizing the name? feel free to file a bug: https://github.com/pypa/conveyor/issues

21:56 <michalrus> It would be more consistent.