fixing duplicated parameter description

there were duplicated parameter definitions for 'err', 'callback.entities', 'callback.nextQuery', 'callback.apiResponse'.

fixed by removing redundant.

CONTRIBUTORS

@@ -18,3 +18,4 @@ Patrick Costello <pcostell@google.com>
 Silvano Luciani <silvano@google.com>
 Stephen Sawchuk <sawchuk@gmail.com>
 Anand Suresh <anandsuresh@gmail.com>
+Hector Rovira <hrovira@gmail.com>

lib/datastore/request.js

@@ -552,17 +552,10 @@ DatastoreRequest.prototype.delete = function(keys, callback) {
  *     stream instance is returned.
  * @param {?error} callback.err - An error returned while making this request
  *     (may be null).
- * @param {array} callback.entities - The list of entities returned by this
- *     query. Note that this is a single page of entities, not necessarily
- *     all of the entities.
- * @param {?module:datastore/query} callback.nextQuery - If present, run another
- *     query with this object to check for more results.
- * @param {object} callback.apiResponse - The full API response.
- * @param {?error} callback.err - An error returned while making this request
  * @param {object[]} callback.entities - A list of entity objects which match
  *     the provided keys.
- * @param {?object} callback.nextQuery - If present, query with this object to
- *     check for more results.
+ * @param {?module:datastore/query} callback.nextQuery - If present, run another
+ *     query with this object to check for more results.
  * @param {object} callback.apiResponse - The full API response.
  *
  * @example