- Make full use of Meson's Python module.
- Drop python_incdir option. It's now possible to use a .pc file to
specify the include path.
- Drop config.h, as we only needed it for HAVE_MACOS, which we can
easily check for in the single location that we need it.
Most use-cases will need to use some JS API that we're not bridging, so
it's better to keep our bindings simple.
It has also become clear that our CLI tools should be split out so Frida-based
tools don't have to depend on colorama, prompt_toolkit, and pygments.