Add option to skip the devstack exercises.

Change-Id: Iff1bed6ca61fdf4bca979aced4f0d287eda9fb19

devstack-vm-gate-wrap.sh

@@ -329,6 +329,9 @@ fi
 # Set to 1 to run the Tempest test suite
 export DEVSTACK_GATE_TEMPEST=${DEVSTACK_GATE_TEMPEST:-0}
 
+# Set to 0 to skip the devstack exercises
+export DEVSTACK_GATE_EXERCISES=${DEVSTACK_GATE_EXERCISES:-1}
+
 # Set to 1 to run postgresql instead of mysql
 export DEVSTACK_GATE_POSTGRES=${DEVSTACK_GATE_POSTGRES:-0}
 

devstack-vm-gate.sh

@@ -219,8 +219,10 @@ else
     echo "Removing sudo privileges for devstack user"
     sudo rm /etc/sudoers.d/50_stack_sh
 
-    echo "Running devstack exercises"
-    sudo -H -u stack ./exercise.sh
+    if [ "$DEVSTACK_GATE_EXERCISES" -eq "1" ]; then
+        echo "Running devstack exercises"
+        sudo -H -u stack ./exercise.sh
+    fi
 fi
 
 if [ "$DEVSTACK_GATE_TEMPEST" -eq "1" ]; then