wip api-v3: add error handler middleware and custom error classes

website/src/middlewares/api-v3/index.js

@@ -0,0 +1,11 @@
+'use strict';
+
+// This module is only used to attach middlewares to the express app
+
+let errorHandler = require('./errorHandler');
+
+module.exports = function (app) {
+
+  // Error handler middleware, define as the last one
+  app.use(errorHandler);
+};