Updated openstack/openstack
Project: openstack/neutron  d3dfbf3e500a30d88f1c08664204dfc118a0154c

Use dict_extend_functions to populate provider network attributes

Use dict_extend_functions mechanism to handle populating additional
provider network attributes into Network model in Nuage plugin.

Change-Id: I72e5afe3d03ae223fcd8e75f1f4f07624c3a7daf
Closes-Bug: #1362308