When downloading a python package from the PyPI repository the links
where pointing to a non-existent parent directory, thus breaking the
packages. The files don't ever change, and are really simple, so let's
just materialize them.
They're almost entirely autogenerated, and we use symlinks into the
top directory to reduce replication.
They can't be under pyln.spec.message, because a package can't also
be a namespace.
We also add fulltext and desc fields, and exclude our "gen" files from
flake8, since the spec quotes contain weird whitespace.
Changelog-Added: Python: pyln.spec.bolt{1,2,4,7} packages.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
