Support setting explicit ports for jobs

Signed-off-by: Lewis Marshall <lewis@lmars.net>
Support a "tcp_ports" key in manifest.json to forward explicit ports

Signed-off-by: Lewis Marshall <lewis@lmars.net>
Start discoverd on well known port 1111

Signed-off-by: Lewis Marshall <lewis@lmars.net>
Merge pull request #10 from flynn/explicit-ports

Support explicit ports