set relative route to user model

src/libs/routes/user.js

@@ -8,7 +8,7 @@ const config = require(`${libs}/config`);
 
 const log = require(`${libs}/log`)(module);
 
-const User = require('../models/user');
+const User = require(`${libs}/models/user`);
 
 const jwt = require('jwt-simple');
 
@@ -55,7 +55,7 @@ userApp.post('/authenticate', (req, res) => {
         if (err) throw err;
 
         if(!user){
-            res.send({success: false, msg: 'Authentication failed. User not found.'});
+            res.json({success: false, msg: 'Authentication failed. User not found.'});
         }
         else {
             user.comparePassword(req.body.password, (err, isMatch) => {