增加RequestContainer对象，包含请求中的request，response，session，pageContext对象，可以通静态方法过RequestContextHolder.getRequestContainer()获取RequestContainer实例
增加session获取方法
增加一组获取request，response，pageContext，session的静态方法
public static HttpServletResponse getResponse()
{
	RequestContainer requestContainer = getRequestContainer();
	return requestContainer != null?requestContainer.getResponse():null;
}
public static PageContext getPageContext()
{
	RequestContainer requestContainer = getRequestContainer();
	return requestContainer != null?requestContainer.getPageContext():null;
}
public static HttpServletRequest getRequest() 
{
	RequestContainer requestContainer = getRequestContainer();
	return requestContainer != null?requestContainer.getRequest():null;
}
public static HttpSession getSession(boolean create) 
{
	RequestContainer requestContainer = getRequestContainer();
	return requestContainer !=
null?requestContainer.getSession(create):null;
}