code: public Result<Void> addDescription(AuthzTrans trans, String ns, String type, 
  			String instance, String action, String description) {
  		//TODO Invalidate?
  		return dao().addDescription(trans, ns, type, instance, action, description);
  	}
docs: Add desciption to this permission
  
  @param trans
  @param ns
  @param type
  @param instance
  @param action
  @param description
  @return