code: public boolean hasChild(String name)
    {
      Params.notNullOrEmpty(name, "Child name");
      for(Config child : children) {
        if(child.name.equals(name)) {
          return true;
        }
      }
      return false;
    }
docs: Test if configuration object has at least a child with requested name.
  
  @param name child name.
  @return true if configuration object has at least one child with requested name.
  @throws IllegalArgumentException if <code>name</code> argument is null or empty.