Use res.attachment to change csv name

Closes simcaq/SCRUM#42

src/libs/middlewares/response.js

@@ -9,6 +9,7 @@ function response(value) {
     return (req, res, next) => {
         log.debug(req.query.format);
         if (req.query.format === 'csv') {
+            res.attachment(`${value}.csv`);
             res.csv(req.result);
         } else if (req.query.format === 'xml') {
             res.send(xml('result', JSON.stringify({ [value]: req.result })));