issue2550966: fix suboptimal links in docs. I think I got the majority of them. Some links still don't resolve because they are gone and there is no replacement afaict. Also the check is picking up example links like: https://.../rest and http://localhost:8017/... which should not be checked but are.

from roundup.dist.command.build import build_message_files, check_manifest
from distutils.command.install_lib import install_lib as base

class install_lib(base):

    def run(self):
        check_manifest()
        build_message_files(self)
        base.run(self)