Log Message:
Update ruby-multi_json to 1.7.0.

1.7.0
-----
* [Add load_options/dump_options to \ 
MultiJson](https://github.com/intridea/multi_json/commit/a153956be6b0df06ea1705ce3c1ff0b5b0e27ea5)
* [MultiJson does not modify \ 
arguments](https://github.com/intridea/multi_json/commit/58525b01c4c2f6635ba2ac13d6fd987b79f3962f)
* [Enable quirks_mode by default for json_gem/json_pure \ 
adapters](https://github.com/intridea/multi_json/commit/1fd4e6635c436515b7d7d5a0bee4548de8571520)
* [Add JrJackson \ 
adapter](https://github.com/intridea/multi_json/commit/4dd86fa96300aaaf6d762578b9b31ea82adb056d)
* [Raise ArgumentError on bad adapter \ 
input](https://github.com/intridea/multi_json/commit/911a3756bdff2cb5ac06497da3fa3e72199cb7ad)