Merge pull request #6697 from alainsahli/master

add empty namespace declaration for chai-as-promised to allow es6 imports

chai-as-promised/chai-as-promised.d.ts

@@ -8,6 +8,7 @@
 
 declare module 'chai-as-promised' {
     function chaiAsPromised(chai: any, utils: any): void;
+    namespace chaiAsPromised {}
     export = chaiAsPromised;
 }