packet_filer: default proto to icmp

Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
neutron2snabb: get vlan parameter from zone_vlan field

Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Merge pull request #319 from virtualopensystems/misc_fixes

Misc fixes