teststeps: Improvements of step driven TC

teststeps: Improvements of step driven TC

This patch adds support of access to VMs deployed automatically
by deployment scenario (e.g. pvp, pvvp4, etc.). It also modifies
filter for checking output of executed commands to correctly
handle different end of line encodings (i.e. \n vs. \n\r).

JIRA: VSPERF-539

Change-Id: Ifc796d992b90e316bad5853aaefce79e439e294d
Signed-off-by: Martin Klozik <martinx.klozik@intel.com>
Reviewed-by: Al Morton <acmorton@att.com>
Reviewed-by: Christian Trautman <ctrautma@redhat.com>
Reviewed-by: Sridhar Rao <sridhar.rao@spirent.com>
Reviewed-by: Trevor Cooper <trevor.cooper@intel.com>