clarify applyEach docs. Closes #1501

lib/applyEach.js

@@ -6,7 +6,9 @@ import map from './map';
  * `callback` after all functions have completed. If you only provide the first
  * argument, `fns`, then it will return a function which lets you pass in the
  * arguments as if it were a single function call. If more arguments are
- * provided, `callback` is required while `args` is still optional.
+ * provided, `callback` is required while `args` is still optional. The results
+ * for each of the applied async functions are passed to the final callback
+ * as an array.
  *
  * @name applyEach
  * @static
@@ -25,7 +27,10 @@ import map from './map';
  * arguments, `callback` is required.
  * @example
  *
- * async.applyEach([enableSearch, updateSchema], 'bucket', callback);
+ * async.applyEach([enableSearch, updateSchema], 'bucket', (err, results) => {
+ *     // results[0] is the results for `enableSearch`
+ *     // results[1] is the results for `updateSchema`
+ * });
  *
  * // partial application example:
  * async.each(