Remove references to _.

sum.js

@@ -5,14 +5,13 @@ import identity from './identity.js';
  * Computes the sum of the values in `array`.
  *
  * @static
- * @memberOf _
  * @since 3.4.0
  * @category Math
  * @param {Array} array The array to iterate over.
  * @returns {number} Returns the sum.
  * @example
  *
- * _.sum([4, 2, 8, 6]);
+ * sum([4, 2, 8, 6]);
  * // => 20
  */
 function sum(array) {