Disable dhcp_domain distribution when dhcp_domain is empty

fixes bug 1099625

Change-Id: Ib86770345c46a0dd8bb38a4c3e435420170828af
Enable OVS and NETNS utilities to perform logging

Fixes bug 1118517

Change-Id: I041e61505475da2383b34eaeb16dd3b0e9750898
only destroy single namespace if router_id is set

Fixes bug 1122206

If multiple instances of l3_agent are running on the same host, all qrouter-
namespaces will be destroyed as new l3_agents are started.  This fix allows
for multiple l3_agents to be running on the same host when router_id is set
for each agent.

Change-Id: I879cdc6faba94900f831232232d67e471c70d778
Merge "Enable OVS and NETNS utilities to perform logging" into stable/folsom
Shorten the DHCP default resync_interval

Fixes bug 1128180

Change-Id: Ie63ef674b5e05fab659e675774a1b25cd57d4c41
Merge "Disable dhcp_domain distribution when dhcp_domain is empty" into stable/folsom
Merge "Shorten the DHCP default resync_interval" into stable/folsom