Fixes to make STC runs more reliable

- make sure that ONOS_USE_SSH is set in the environment
- only wipe out data once mininet finishes shutting down

Change-Id: I6dfcd2c839cc00a975583cb93f16775d5fcadf94
diff --git a/tools/test/scenarios/net-setup.xml b/tools/test/scenarios/net-setup.xml
index e179ec5..13252d0 100644
--- a/tools/test/scenarios/net-setup.xml
+++ b/tools/test/scenarios/net-setup.xml
@@ -17,9 +17,9 @@
     <!-- TODO: parametrize this via recipes -->
     <group name="Net-Setup">
         <step name="Push-Topos" exec="onos-push-topos ${OCN}"/>
-        <step name="Stop-Mininet-If-Needed" env="~" exec="onos-mininet stop"/>
 
-        <step name="Wipe-Out-Data-Before" exec="onos-wipe-out"/>
+        <step name="Stop-Mininet-If-Needed" env="~" exec="onos-mininet stop"/>
+        <step name="Wipe-Out-Data-Before" exec="onos-wipe-out" requires="^"/>
 
         <step name="Initial-Summary-Check" requires="~Wipe-Out-Data-Before"
               exec="onos-check-summary ${OC1} [0-9]* 0 0 0"/>
@@ -43,4 +43,4 @@
         <step name="Check-Flows" requires="~Pause-For-Masters,~Check-Summary"
               exec="onos-check-flows ${OC1}"/>
     </group>
-</scenario>
\ No newline at end of file
+</scenario>
diff --git a/tools/test/scenarios/prerequisites.xml b/tools/test/scenarios/prerequisites.xml
index 650aa41..2c541d5 100644
--- a/tools/test/scenarios/prerequisites.xml
+++ b/tools/test/scenarios/prerequisites.xml
@@ -15,7 +15,7 @@
   -->
 <scenario name="prerequisites" description="ONOS test pre-requisites">
     <group name="Prerequisites">
-        <step name="Check-Environment" exec="test -n ${ONOS_ROOT} -a -n ${ONOS_NIC} -a -n ${OC1}"/>
+        <step name="Check-Environment" exec="test -n ${ONOS_ROOT} -a -n ${ONOS_NIC} -a -n ${OC1} -a '${ONOS_USE_SSH}' == 'true'"/>
         <step name="Check-ONOS-Bits" exec="onos-check-bits"/>
 
         <parallel var="${OC#}">