reporting: add vswitch, vnf and trafficgen version into the report

reporting: add vswitch, vnf and trafficgen version into the report

Final test report MD file should contain information about version
of vswitch, vnf, VM loopback forwarding application and traffic
generator used during the test. In case that component is cloned
from GIT repository, then hash of its recent commit should be
part of the report too.

Change-Id: I4eb398bc95bc5030d0852d08bcf9febbf17640d4
JIRA: VSPERF-172
Signed-off-by: Martin Klozik <martinx.klozik@intel.com>
Reviewed-by: Maryam Tahhan <maryam.tahhan@intel.com>
Reviewed-by: Radek Zetik <radekx.zetik@intel.com>
Reviewed-by: Al Morton <acmorton@att.com>
Reviewed-by: Brian Castelli <brian.castelli@spirent.com>
Reviewed-by: Tv Rao <tv.rao@freescale.com>