SportletProperties conatins all the "hidden" variable names
that get transmitted between the portlet container and the portlets to
request a particular portlet lifecycle action.
SportletProperties comtains three kinds of attributes
Lifecycle atttributes specify the lifecycle method to invoke on a
portlet
Portlet object attributes contain the actual portlet object e.g.
PortletConfig, PortletSettings which must be transferred in the
servlet request.