code: boolean foundGroupFormat(Map<String,?> map, String pkgFormat) {
          if (map.containsKey(pkgFormat)) {
              configuration.message.error("doclet.Same_package_name_used", pkgFormat);
              return true;
          }
          return false;
      }
docs: Search if the given map has given the package format.
  
  @param map Map to be searched.
  @param pkgFormat The pacakge format to search.
  
  @return true if package name format found in the map, else false.