Add "gongo/json-reformat" recipe

json-reformat.el is reformat tool for [JSON](http://en.wikipedia.org/wiki/JavaScript_Object_Notation)

e.g.

```
M-x json-reformat-region
```

![](https://github.com/gongo/json-reformat/raw/master/images/json-reformat-1-before.png)

![](https://github.com/gongo/json-reformat/raw/master/images/json-reformat-1-after.png)