Redeclaration of 'should_continue' is hidding external variable
main.lua: Add command-line argument for debugging purposes.

  * -dm = Enable developer mode. Enables debug prints and asserts.

  * This sets to true a global variable _G.developer_debug that can be
    used on the rest of snabswitch to enable prints, asserts or other
    things that are not intended for production.

  * Make all other parts of snabswitch where a debug variable was used
    (or should be used) to depend on this one.
Only print the last_size when debug is enabled (./snabbswitch -dm).

 * This code starts triggering on a kernel >= 3.14 (Ubuntu 14.04 uses
   3.13, so this went unnoticed). It causes a lot of flood because it
   triggers constantly.

 * Example of the output from snabswitch when running same_vlan.ports
   with both VMs running Kernel 3.14.23 and running an iperf test
   (MTU 1500) between both VMs:

      size=  2036
      size=  1524
      size=  2036
      size=  1524
      size=  2036
      size=  1524
      [ .... repeated ad-infinitum ]

 * I have bisected the Linux kernel, the commit that causes this print to
   trigger is fb51879dbceab9c40a39018d5322451691909e15 (merged on 3.14)
   https://git.kernel.org/linus/fb51879
NFV config: fix function load

 - pass t.port_id do virtio
 - create filter only if there are actually rules (# is >0)

Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
neutron2snabb: fix filter generation

 - we do not support filters based on remote_group_id, jsut drop those
 - return an empty list when there are no valid rules found

Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
snabbnfv-traffic: apply config on each internal iteration

Before it was 60 seconds - too slow

Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Merge pull request #325 from virtualopensystems/misc_fixes

Misc fixes
Merge pull request #315 from dpino/fix-should-continue

Redeclaration of 'should_continue' is hidding external variable
Merge pull request #324 from clopez/last_size-check-debug

Add command-line argument for debugging purposes (-dm) and only print the last_size info when debug is enabled