JSON ParseException should be more verbose

[watzon]

This is a request, and something I'd be happy to look at implementing myself. JSON ParseExceptions are pretty basic as far as the information that is given and can make debugging pretty difficult with extremely large blocks of json. For example, I'm getting parse exceptions at 1:22400. It would be nice if we could maybe make the error somewhat like SQL's errors where they say near 'SELECT * FROM your_mom'.