Add webpack code splitting module

Add cold-module replacement
Add webpack module hashing

server/server.js

@@ -10,6 +10,22 @@ var _ = require('lodash'),
     path = require('path'),
     setupPassport = require('./component-passport');
 
+// polyfill for webpack bundle splitting
+const requireProto = Object.getPrototypeOf(require);
+if (!requireProto.hasOwnProperty('ensure')) {
+  Object.defineProperties(
+    requireProto,
+    {
+      'ensure': {
+        value: function ensure(modules, callback) {
+          callback(this);
+        },
+        writable: false,
+        enumarble: false
+      }
+    }
+  );
+}
 Rx.config.longStackSupport = process.env.NODE_DEBUG !== 'production';
 var app = loopback();
 var isBeta = !!process.env.BETA;