Port hide srvr addresses extension to v3 API Pt2

Ports the hide server addresses extension and the corresponding
unittests to the v3 framework.

Partially implements blueprint nova-v3-api

Change-Id: If0df9839d897b7baf49278915f1a4948c8b6a1e4
Merge "Port hide srvr addresses extension to v3 API Pt2"