TCP and UDP ports with the same number can not simultaneously be forwarded

[bitglue]

This appears to be a regression of #1108 and also described at https://groups.google.com/forum/#!msg/vagrant-up/zK578M3qnKw/k9dZkiQkzNcJ

$ vagrant --version
Vagrant 1.7.2

  config.vm.define 'statsite' do |statsite|
    statsite.vm.network 'forwarded_port', guest: 8125, host: 8125, protocol: 'udp'
    statsite.vm.network 'forwarded_port', guest: 8125, host: 8125, protocol: 'tcp'
    statsite.vm.provider 'docker' do |d|
      d.build_dir = 'dockerfiles/statsite'
      d.name = 'statsite'
      d.link 'carbon-cache:carbon'
    end
  end

results in

$ docker ps
CONTAINER ID  IMAGE         COMMAND               CREATED         STATUS         PORTS                                                      NAMES
81e1f44083f1  0d27e166f52b  "/usr/local/bin/stat  52 minutes ago  Up 52 minutes  8125/udp, 0.0.0.0:8125->8125/tcp                           statsite

If the order of the 'forwarded_port's is exchanged, then it will forward UDP but not TCP.

[sethvargo]

I think this is the same thing as #5602 actually