can not run app generated by koa2
I tried 

```
koa2 --hbs --css sass --git koa2-test
```

Install works fine 
https://gist.githubusercontent.com/AubreyHewes/fa6881ecd9089482ccc5a26f0ad2e126/raw

Running `npm start` works fine
https://gist.githubusercontent.com/AubreyHewes/3498e3ec955cf04ced5cf09e32865b22/raw
- though handlebars layout is not used (outputs only  the `index.hbs`)
- though sass middleware is not used (maybe due to the layout not being used?)

**Running `npm run koa` fails...**
https://gist.githubusercontent.com/AubreyHewes/20f64418bf61213078ad171296a9ee59/raw

So I installed the failing module `babel-plugin-add-module-exports`.. then it fails on `babel-plugin-transform-es2015-modules-commonjs`..
https://gist.githubusercontent.com/AubreyHewes/972d7b3c031d8a59bff1f34dad94e387/raw

So I installed the failing module `babel-plugin-transform-es2015-modules-commonjs` .. it still fails on the same module  `babel-plugin-transform-es2015-modules-commonjs`..
https://gist.githubusercontent.com/AubreyHewes/b5bee5ee974c10fbe2f7c3e26d1845d7/raw

I assume it's just not ready for what I tried..
I looked into it a little and koa-views does not seem to support handlebars layouts.. 

```
Linux 4.2.0-36-generic #42-Ubuntu SMP Thu May 12 22:05:35 UTC 2016 x86_64 x86_64
node: v5.12.0
npm: 3.8.6
```

Any tips appreciated, thanks.
