DHCP CPNR with Relay integration

OpenStack deployments have encountered significant weaknesses with the default implementation of DHCP provided by neutron - OpenStack's networking component. One such weakness has been availability of the DHCP service. When the DHCP service is not available, new VMs cannot be started successfully. In an effort to make the DHCP service more robust (and therefore more available), we propose that an additional DHCP driver be provided such that operators can options as to operational DHCP, such as Cisco’s DHCP product: Cisco Prime Network Registrar (CPNR). In addition, a dhcp relay will be developed such to handle larger networks, this will be necessary for DHCP clients on subnets not directly servered by DHCP servers, DHCP relay agent will be install on these subnets. The DHCP relay will be generic in that it will be able to be used with any DHCP server.