[docs] Fixed beforeBulkUpdate explanation.

lib/hooks.js

@@ -334,7 +334,7 @@ Hooks.hasHooks = Hooks.hasHook;
  */
  */
 
 
 /**
 /**
- * A hook that is run after updating instances in bulk
+ * A hook that is run before updating instances in bulk
  * @param {String}   name
  * @param {String}   name
  * @param {Function} fn   A callback function that is called with options
  * @param {Function} fn   A callback function that is called with options
  * @name beforeBulkUpdate
  * @name beforeBulkUpdate