A note for next time we're updating the manylinux definitions:

Distrowatch has an amazing set of tables showing which versions of
which distros ship which libraries. So if you want to know the answer
to questions like "which versions of debian have a glibc that is newer
than the one in RHEL 7", then here you go:

https://distrowatch.com/table.php?distribution=redhat
https://distrowatch.com/table.php?distribution=debian
https://distrowatch.com/table.php?distribution=ubuntu

etc.
Add a note about Distrowatch's amazing distro version tables
Add a note about Distrowatch's amazing distro version tables

Just came across these and want to make sure I save the link somewhere
where we can find it when it's time to do manylinux2. Not sure what the
best place is, but this seems like a reasonable option?
