CLEREZZA-270: clanged renderlet api

[Reto Bachmann-Gmuer]

the render method has an additional argument: sharedRenderingValues.
This is a map that can be used by different renderlets involved in the
rendering of a response to share values.

the new siganuture is:

public void render(GraphNode res,
                        GraphNode context,
                        Map<String, Object> sharedRenderingValues,
                        CallbackRenderer callbackRenderer,
                        URI renderingSpecification,
                        String mode,
                        MediaType mediaType,
                        RequestProperties requestProperties,
                        OutputStream os) throws IOException;

cheers,
reto