[types-02] Sequelize - Import Promise for target < es6 (#10862)

* import Promise for target < es6

* Fix test Promise type

sequelize/index.d.ts

@@ -11,6 +11,7 @@
 
 
 import * as _ from "lodash";
+import * as Promise from "bluebird";
 
 declare namespace sequelize {
 

sequelize/sequelize-tests.ts

@@ -1,4 +1,5 @@
 import Sequelize = require("sequelize");
+import Promise = require('bluebird');
 
 //
 //  Fixtures