code: public static String toKind(Class<?> clazz) {
  		if (clazz.getAnnotation(org.eiichiro.acidhouse.Entity.class) == null) {
  			throw new IllegalArgumentException("Entity class [" + clazz
  					+ "] must be annotated by @org.eiichiro.acidhouse.Entity");
  		}
  		
  		return clazz.getSimpleName();
  	}
docs: Translates {@code Class} to Google App Engine Datastore entity's kind
  name.
  
  @param clazz The {@code Class} of Acid House entity.
  @return The kind name translated from Acid House entity class.