code: protected CheckGroupSelector newCheckGroupSelector(final String id, final CheckGroup<T> group)
  	{
  		return ComponentFactory.newCheckGroupSelector(id, group);
  	}
docs: Factory method for create a new {@link CheckGroupSelector}. This method is invoked in the
  constructor from the derived classes and can be overridden so users can provide their own
  version of a new {@link CheckGroupSelector}.
  
  @param id
  the id
  @param group
  the {@link CheckGroup}
  @return the new {@link CheckGroupSelector}