Add attributes for cookbook-openstack-network

Add attributes for cookbook-openstack-network to sync the latest neutron
configuration for database.

Implements: blueprint neutron-ml2
Change-Id: I1fb5cf77ab7a2d700dbd72915fc30a7b176b8ca2
Refactoring chefspec tests

Change-Id: I35dfca684039512e2a238466ff7df5f3fd34d956
Addresses: blueprint refactor-spec-files
Closes-Bug: 1282996
Merge "Add attributes for cookbook-openstack-network"
Merge "Refactoring chefspec tests"