Consider accepting string formatted in JSON instead of JavaScript object for src

[renamartins]

Consider also accepting a string in JSON format instead of one having to JSON.parse(theJsonString) beforehand.

[Karanpal97]

@renamartins hey i used the lib but it have the issue the issue is when i send the data in string and when i parse it before sending source that is by JSON.parse then the collapsing functionallty is not working ??