Functional Tests [1/3]: Added module for dummy nics

Added setLinkUpDummy, setLinkDownDummy, setIPDummy
These methods will be used in an upcoming test

Change-Id: I1c7ed4110cd8d45a3fb7a9cc2cd2dc07004e96b9
Signed-off-by: Assaf Muller <amuller@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/18039
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Reviewed-by: Giuseppe Vallarelli <gvallare@redhat.com>
Tested-by: Giuseppe Vallarelli <gvallare@redhat.com>