Fix imports, testing with roles, list of verbs

This pul request adds a few features to helpers:

- Fix import for except
- Add support for testing with user roles
- Add support for list of verbs
If I read the diff correctly, then this is a breaking change. Please modify the new function to support the old API (`verb` instead of `verbs`) too.

E.g.

```js
if (typeof verbs === 'string') {
  verbs = [verbs];
}
```