Update package.json

xml-crypto changed xpath implementation on version 0.0.14 and it is throwing method not found:

TypeError: Object function SelectNodes(doc, xpath)
{
var parser = new XPathParser();
var xpath = parser.parse(xpath);
var context = new XPathContext();
if(doc.documentElement){
context.expressionContextNode = doc.documentElement;
} else {
context.expressionContextNode = doc;
}
var res = xpath.evaluate(context)

return res.toArray();
} has no method 'SelectNodes'
at SAML.validateSignature (/passport-saml/lib/passport-saml/saml.js:158:35)