fixing image_inspector_tool's handling of visible=False
fixing image_inspector_tool's handling of visible=False

burnpanck/chaco,burnpanck/chaco,tommy-u/chaco,tommy-u/chaco,tommy-u/chaco,ContinuumIO/chaco,ContinuumIO/chaco,ContinuumIO/chaco,burnpanck/chaco,ContinuumIO/chaco