Add Neutron CLI tests to tempest
Add Neutron CLI tests to tempest

Basic, read-only tests for Neutron CLI client.
Checks return values and output of read-only commands.

Change-Id: I5384e063686d21f006f8837cd916177e3d490bd6

afaheem88/tempest-lib,varunarya10/tempest-lib,cneill/tempest-lib,sorenh/tempest-lib,JioCloud/tempest-lib,mtreinish/tempest-lib