Draft: Add support for building with Meson

This adds a super basic meson.build that mostly matches what configure/make.

There is a good deal of python cleanup in here as well, since I needed to make some changes to the script anyway to make it work with Meson.

Notably, this does not handle exporting symbols since the current approach relies on using libtool. Meson doesn't use libtool, so we'll need to migrate to using __attribute__((...)) instead.

Also, doesn't have CI integration