code: public static Provider<String> bindDefault(Binder binder, String propertyName, String defaultValue) {
          Key<String> propertyKey = getPropertyKey(propertyName);
          OptionalBinder<String> optionalBinder = OptionalBinder.
                  newOptionalBinder(binder, propertyKey);
          optionalBinder.setDefault().toInstance(defaultValue);
          return binder.getProvider(propertyKey);
      }
docs: Binds default value to specified property
  
  @param binder       Guice's Binder
  @param propertyName Name of property
  @param defaultValue Default value
  @return Provider to new bound value