code: public Content getContent(String key, Object o0, Object o1) {
          return getContent(key, o0, o1, null);
      }
docs: Gets a {@code Content} object, containing the string for
  a given key in the doclet's resources, formatted with
  given arguments.
  
  @param key the key for the desired string
  @param o0  string or content argument to be formatted into the result
  @param o1  string or content argument to be formatted into the result
  @return a content tree for the text