Adds a name-value pair to the query string parameters of outgoing request.
oauth.addParam(paramName, paramValue, [callback])
The 'callback' parameter specifies a function which will be called when the operation completes (or an error is encountered). If the 'callback' parameter is not specified, then the method will block and will not return until the operation completes (or an error is encountered).
The callback for this method is defined as:
'err' is the error that occurred. If there was no error, then 'err' is 'null'.
'err' has 2 properties which hold detailed information:
This method can be used to add query string parameters to the outgoing request. One common use for this method would be to add the "state" parameter to the request, which can be used when the ClientProfile is cfWebServer to add user defined data. The authorization server will include the "state" parameter in the response and will be available in the post back to your server which will allow you to maintain state in your application.