Remove references to _.

uniqueId.js

@@ -8,16 +8,15 @@ let idCounter = 0;
  *
  * @static
  * @since 0.1.0
- * @memberOf _
  * @category Util
  * @param {string} [prefix=''] The value to prefix the ID with.
  * @returns {string} Returns the unique ID.
  * @example
  *
- * _.uniqueId('contact_');
+ * uniqueId('contact_');
  * // => 'contact_104'
  *
- * _.uniqueId();
+ * uniqueId();
  * // => '105'
  */
 function uniqueId(prefix) {