Problem files js/ts

[matheo]

Ionic 2 now focused its efforts on TypeScript only, learn to use it, it’s easy

Ionic 2 cli and Javascript 2015 / ES6

AFAIK it’s not possible anymore, here’s the official comment on the topic: JS option has been removed, since we are going to focus our efforts to support Typescript. Since TS is a superset of JS, it is up to developers to use the new features or not. We strongly recommend to give TS a try, decorators and types help a lot while using angular 2.