Add missing test for useful values showing up in used_ports in the result of `marshal_configuration`.
Add missing test for useful values showing up in used_ports in the result of `marshal_configuration`.

lukemarsden/flocker,lukemarsden/flocker,adamtheturtle/flocker,w4ngyi/flocker,Azulinho/flocker,moypray/flocker,Azulinho/flocker,mbrukman/flocker,adamtheturtle/flocker,wallnerryan/flocker-profiles,agonzalezro/flocker,lukemarsden/flocker,1d4Nf6/flocker,runcom/flocker,achanda/flocker,w4ngyi/flocker,hackday-profilers/flocker,LaynePeng/flocker,hackday-profilers/flocker,adamtheturtle/flocker,moypray/flocker,runcom/flocker,AndyHuu/flocker,Azulinho/flocker,wallnerryan/flocker-profiles,w4ngyi/flocker,mbrukman/flocker,jml/flocker,wallnerryan/flocker-profiles,jml/flocker,agonzalezro/flocker,LaynePeng/flocker,moypray/flocker,1d4Nf6/flocker,AndyHuu/flocker,agonzalezro/flocker,jml/flocker,AndyHuu/flocker,1d4Nf6/flocker,mbrukman/flocker,LaynePeng/flocker,achanda/flocker,achanda/flocker,hackday-profilers/flocker,runcom/flocker