Python packaging targets

> 1. Distros should be much happier having multiple versions of the same package available, with suitable cleverness to provide the "correct' version to any software that runs

Distros are already fundamentally able to do this in the general sense, but the individual languages/runtimes/whatever need to support [semantically] versioned package namespaces, and enforce that through culture... and tooling that does the right thing by default.