Add Support for Line Numbers on Valid JSON

[esheri3]

I am considering using this library to facilitate syntax highlighting capabilities. I understand you currently report line / col numbers for syntax errors. However, I am interested in reporting errors on well-formed JSON documents and I'd like to be able to reference the line/col information within the document. For example...

{ "name": "test123" }

... is a valid JSON document, but my program would report an error stating that "name must only contain letters", and thus I would like to be able to lookup the line number for the 'name' property and visually highlight it. Is providing such information something you would consider?