code: public <T> DynamicContextualProperty<T> getContextualProperty(String propName, T defaultValue) {
          return getContextualProperty(propName, defaultValue, null);
      }
docs: Create a new contextual property of type T
  
  @param propName     property name
  @param defaultValue default value if the property is not defined in underlying configuration
  @param <T>          the type of the property value