Simple TCP proxy to simulate TLS and PROXY protocol locally
$ docker run -link <container>:host -p <outer-port> convox/proxy <outer-port> <container-port> <protocol> [options...]
$ docker run -link foo:host -p 80 convox/proxy 443 5000 https
$ docker run -link foo:host -p 443 convox/proxy 443 5000 https
$ docker run -link foo:host -p 443 convox/proxy 443 5000 https secure
$ docker run -link foo:host -p 443 convox/proxy 443 5002 tls secure proxy