Update git submodules

Update git submodules

* Update docs/submodules/samplevnf from branch 'master'
  - Merge "Fixed the calculation of dropped packets and other changes"
  - Fixed the calculation of dropped packets and other changes

    * Calculation of aboslute and relative dropped packets was wrong and is
    now fixed.
    * ./createrapid.py has now an extra option to select custom availability
    zones for the different VMs.
    * Fixed a typo to create the flavor: hw:cpu_thread_policy
    * The generator config files have now the packet id & signature fields.
    See PROX for more details on this.
    * ./runrapid has now a new option --configonly. Default is False. If set
    to True, all configuration files will be copied to the VMS, but the
    tests are not started. This allows you to go to the VMs and manually
    start PROX.
    * In addition to the average latency, maximum latency is now also
    displayed.

    Change-Id: I3bbd7897deb6e452068c07ef68d3959ffa4a4b50
    Signed-off-by: Luc Provoost <luc.provoost@intel.com>