Implements an API sample test for a GET request for os-baremetal-nodes
which was previously manually generated and wrong. Removes api samples
for add-interface, create, and remove-interface which were removed
for os-baremetal-nodes at some point.
This should bring the os-baremetal-nodes plugin in sync with reality
for both v2 and v2.1
Partially implements blueprint v2-on-v3-api
Change-Id: Ibd55b43368485b7f460ef6564f611df136275562
9b794005fe