code: public boolean isFeature(String feature) {
  		Boolean result = features.get(feature);
  		return (result != null) ? result : false;
  	}
docs: Checks the value of the specified feature. Will return false for features
  that have not been specified. Implementations should rely on
  {@link #contains(String)} in addition to this method.
  
  @param feature
  The feature to check
  @return If the feature is true.