Refactors routers to include path

Router.use() is based on path, not router instance.
This means routerA can `.use` a middleware and end up effecting routerB.
The user router (and all others) was running through
the requireToken middleware as a result.

This is a documented issue with express router:
pillarjs/router#38

app/routes/order_routes.js

@@ -82,12 +82,12 @@ const deleteOrder = (req, res, next) => {
 router.use(requireToken)
 
 // Create & Index routes
-router.route('/orders')
+router.route('/')
   .post(createOrder)
   .get(indexOrders)
 
 // Update, Delete, & Show routes
-router.route('/orders/:id')
+router.route('/:id')
   .patch(findOrderMiddleware, updateOrder)
   .get(findOrderMiddleware, showOrder)
   .delete(findOrderMiddleware, deleteOrder)

app/routes/product_routes.js

@@ -6,14 +6,14 @@ const Product = require('../models/product')
 const { handle404 } = require('../../lib/custom_errors')
 
 // INDEX
-router.get('/products', (req, res, next) => {
+router.get('/', (req, res, next) => {
   Product.find()
     .then(products => res.status(200).json({ products }))
     .catch(next)
 })
 
 // SHOW
-router.get('/products/:id', (req, res, next) => {
+router.get('/:id', (req, res, next) => {
   Product.findById(req.params.id)
     .then(handle404)
     .then(product => res.status(200).json({ product }))

server.js

@@ -57,9 +57,9 @@ app.use(express.urlencoded({ extended: true }))
 app.use(requestLogger)
 
 // register route files
-app.use(productRoutes)
-app.use(orderRoutes)
-app.use(userRoutes)
+app.use('/products', productRoutes)
+app.use('/orders', orderRoutes)
+app.use('/auth', userRoutes)
 
 // register error handling middleware
 // note that this comes after the route middlewares, because it needs to be