Execution example::

  tokenize TokenBigram "Fulltext Search" NormalizerAuto
  # [
  #   [
  #     0, 
  #     1337566253.89858, 
  #     0.000355720520019531
  #   ], 
  #   [
  #     {
  #       "position": 0, 
  #       "value": "fulltext"
  #     }, 
  #     {
  #       "position": 1, 
  #       "value": "search"
  #     }
  #   ]
  # ]
