Improving net test tools and scenarios.

Change-Id: I2b53fa7b28e1135d2356ae58d4ee8ac35184d9b8
diff --git a/tools/build/envDefaults b/tools/build/envDefaults
index 6b4cef7..38a1bc1 100644
--- a/tools/build/envDefaults
+++ b/tools/build/envDefaults
@@ -43,3 +43,4 @@
 export ONOS_USER="${ONOS_USER:-sdn}"    # ONOS user on remote system
 export ONOS_GROUP="${ONOS_GROUP:-sdn}"  # ONOS group on remote system
 export ONOS_PWD="rocks"                 # ONOS user password on remote system
+export ONOS_SCENARIOS=$ONOS_ROOT/tools/test/scenarios