GridSphere Portlet Container API Implementation

The GridSphere portlet container implementation provides implementations of the portlet container interfaces. The implementation makes use of the Castor portlet descriptor classes found in {@link org.gridlab.gridsphere.portletcontainer.impl.descriptor} and uses singleton patterns for the implemtation of the {@link org.gridlab.gridsphere.portletcontainer.PortletMessageManager} and {@link org.gridlab.gridsphere.portletcontainer.PortletDataManager} classes.