feat(auth): implement user authentication system

backend/node_modules/text-hex/index.js

@@ -0,0 +1,24 @@
+'use strict';
+
+/***
+ * Convert string to hex color.
+ *
+ * @param {String} str Text to hash and convert to hex.
+ * @returns {String}
+ * @api public
+ */
+module.exports = function hex(str) {
+  for (
+    var i = 0, hash = 0;
+    i < str.length;
+    hash = str.charCodeAt(i++) + ((hash << 5) - hash)
+  );
+
+  var color = Math.floor(
+    Math.abs(
+      (Math.sin(hash) * 10000) % 1 * 16777216
+    )
+  ).toString(16);
+
+  return '#' + Array(6 - color.length + 1).join('0') + color;
+};