Fix index path creation on Windows

Author: joachimvh

lib/handlers/index.js

@@ -3,6 +3,7 @@ module.exports = handler
 const path = require('path')
 const debug = require('debug')('solid:index')
 const Negotiator = require('negotiator')
+const url = require('url')
 
 async function handler (req, res, next) {
   const indexFile = 'index.html'