Refactor Tutum backend to use beam

Docker-DCO-1.1-Signed-off-by: Fernando Mayo <fernando@tutum.co> (github: fermayo)
Cleanup and Enhance Debug

Signed-off-by: John Hopper john.hopper@jpserver.net
Update exposed ports mapping

Docker-DCO-1.1-Signed-off-by: Fernando Mayo <fernando@tutum.co> (github: fermayo)
Merge pull request #87 from fermayo/tutum-beam
Move debug.go to a `debug` sub-package

Signed-off-by: Solomon Hykes <solomon@docker.com>
Merge pull request #91