WIP: Wire together l10n

- [x] Smooth out grunt tasks
- [x] Connect front end localization
- [ ] Add server side localization for index
- [ ] Add endpoint for client side localization at `/1/l10n/client.json`
This is more content server code. I sort of took it at face value. I'll dig through it a bit and see if we can clean it up for our use. I think it might be unnecessary because they were actually renaming server.po to messages.json which we aren't doing.