Make it look closer to standard Transport.DialTLS, because it's good to be
like standard things.
This also allows usage of thrid party TLS stacks, enabling
https://github.com/refraction-networking/utls.Roller integration.
We settled on a powerful, but a bit complicated acl design.
This commit makes a couple of cosmetic improvements. It also removes
http.Transport, which was previously used to dial and write http
requests for insecure GET requests. Now we have to dial manually,
so we can check the access control list.
