(PDB-720) Fix services test with hard coded Jetty port

Fixed this issue by moving code that dynamically picks a free port out
of import-export-roundtrip and into a separate ns. I just switched the
services test to use that code and there should no longer be conflicts.
Merge pull request #1002 from senior/ticket/master/pdb-720-jetty-test-port-conflict

(PDB-720) Fix services test with hard coded Jetty port