Execution example::

  tokenize 'TokenMecab("include_class", true)' '彼の名前は山田さんのはずです。'
  # [
  #   [
  #     0,
  #     1337566253.89858,
  #     0.000355720520019531
  #   ],
  #   [
  #     {
  #       "value": "彼",
  #       "position": 0,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "名詞",
  #         "subclass0": "代名詞",
  #         "subclass1": "一般"
  #       }
  #     },
  #     {
  #       "value": "の",
  #       "position": 1,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "助詞",
  #         "subclass0": "連体化"
  #       }
  #     },
  #     {
  #       "value": "名前",
  #       "position": 2,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "名詞",
  #         "subclass0": "一般"
  #       }
  #     },
  #     {
  #       "value": "は",
  #       "position": 3,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "助詞",
  #         "subclass0": "係助詞"
  #       }
  #     },
  #     {
  #       "value": "山田",
  #       "position": 4,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "名詞",
  #         "subclass0": "固有名詞",
  #         "subclass1": "人名",
  #         "subclass2": "姓"
  #       }
  #     },
  #     {
  #       "value": "さん",
  #       "position": 5,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "名詞",
  #         "subclass0": "接尾",
  #         "subclass1": "人名"
  #       }
  #     },
  #     {
  #       "value": "の",
  #       "position": 6,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "助詞",
  #         "subclass0": "連体化"
  #       }
  #     },
  #     {
  #       "value": "はず",
  #       "position": 7,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "名詞",
  #         "subclass0": "非自立",
  #         "subclass1": "一般"
  #       }
  #     },
  #     {
  #       "value": "です",
  #       "position": 8,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "助動詞"
  #       }
  #     },
  #     {
  #       "value": "。",
  #       "position": 9,
  #       "force_prefix": false,
  #       "force_prefix_search": false,
  #       "metadata": {
  #         "class": "記号",
  #         "subclass0": "句点"
  #       }
  #     }
  #   ]
  # ]
