code: @Deprecated
      public static boolean isResourceFile(final String lcasefn) {
          for (final String ext: supportedResourceExtensions) {
              if (lcasefn.endsWith(ext)) {
                  return true;
              }
          }
          return false;
      }
docs: Return if the file is a resource file by its extension.
  
  @param lcasefn file name in lower case.
  @return {@code true} if file is a resource file, otherwise {@code false}