added missing format method

Author: omricohen

lib/migrate.js

@@ -817,6 +817,10 @@ module.exports = {
     return {filename, info};
 };
 
+const format = function (i) {
+  return parseInt(i, 10) < 10 ? '0' + i : i;
+}; 
+
 const getCurrentYYYYMMDDHHmms = function () {
   const date = new Date();
   return [
@@ -827,7 +831,7 @@ const getCurrentYYYYMMDDHHmms = function () {
     format(date.getUTCMinutes()),
     format(date.getUTCSeconds())
   ].join('');
-}
+};
 
 
 const executeMigration = function(queryInterface, filename, pos, cb)