Revert "Add UT for port-dependent auth function."

This reverts commit 13106e4ab17074182d36abe5a452544efdde4a03.
Revert "Don't require auth on trusted port."

This reverts commit 8cef516f98becd3b74faa9e71d19c7c6334d980f.
Merge pull request #26 from Metaswitch/auth-fun

[Reviewer: Mike] Auth fun