kill all proceses inside all l3-agent's net.namespaces,

that using ip protocol. When l3 agent start/stop.
Also remove unnided namespaces.

Change-Id: I7e5203f6cec646a8b70609f2bf3b785066068aeb
Closes-Bug: #1310926
Merge "kill all proceses inside all l3-agent's net.namespaces,"