feat(auth): implement user authentication system

backend/node_modules/dezalgo/dezalgo.js

@@ -0,0 +1,22 @@
+var wrappy = require('wrappy')
+module.exports = wrappy(dezalgo)
+
+var asap = require('asap')
+
+function dezalgo (cb) {
+  var sync = true
+  asap(function () {
+    sync = false
+  })
+
+  return function zalgoSafe() {
+    var args = arguments
+    var me = this
+    if (sync)
+      asap(function() {
+        cb.apply(me, args)
+      })
+    else
+      cb.apply(me, args)
+  }
+}