Normalize entity name before getting locals

Fixes #1713 for blueprints `http-proxy`, `http-mock`, `app` and `addon`.

The generators were trying to access and modify `options.entity.name` in the `locals` hook, which was called before `normalizeEntityName`, causing them to err out.

```
$ ember g addon
version: 0.0.40-master-84e031b5c0
Cannot call method 'replace' of undefined
```

Is the test I added sufficient?