Enhancement: Json + XML parsing

[jhaddix]

I love the idea of better parsing in files like this. I run into the same problems with unstructured JSON and XML, that Burp doesn't parse out the links that it should, leaving me with incomplete spider coverage ='( There are several libs that can parse JSON and XML. Would be great if I could just export all links with those extensions or content types in Burp and have JSParse do the intelligent link parsing for me in all those.