Revert "StopMonitor action for IM dummy drivers"

This reverts commit b1d2785707.

src/im_mad/dummy/one_im_dummy.rb

@@ -45,7 +45,6 @@ class DummyInformationManager < OpenNebulaDriver
 
         # register actions
         register_action(:MONITOR, method("action_monitor"))
-        register_action(:STOPMONITOR, method("stop_monitor"))
     end
 
     # Execute the sensor array in the remote host
@@ -73,10 +72,6 @@ class DummyInformationManager < OpenNebulaDriver
 
         send_message("MONITOR", RESULT[:success], number, results)
     end
-
-    def stop_monitor(number, host)
-        send_message("STOPMONITOR", RESULT[:success], number, nil)
-    end
 end