traceroute does not work with L3 DVR

By default the traceroute tool uses UDP packets sent to an "unlikely used port" and receives ICMP TTL expired packets in response. The tool can also be configured to use TCP or ICMP. Currently, none of these methods are supported by the L3 DVR implementation. In the case of ICMP, resolving OVSDB-191 will work for traceroute as well. However, UDP and TCP methods require a different resolution.