code: public Elements getElementsByAttributeValueNot(String key, String value) {
          return Collector.collect(new Evaluator.AttributeWithValueNot(key, value), this);
      }
docs: Find elements that either do not have this attribute, or have it with a different value. Case insensitive.
  
  @param key name of the attribute
  @param value value of the attribute
  @return elements that do not have a matching attribute