Storing google oauth api keys in a seperate config file

Hi Edgar,

I thought I'd move the Google OAuth keys into a seperate file called google_oauth.yml in the config folder, so that it can be gitignored and the keys not put out into the public domain. The thing is that now we are using a public repo, anyone could potentially use the API keys that you've got in the environment files, so while that was fine before I think that the following approach would be better. Consider using this on your project.

The YAML file would look like this:

```
development:
  google_app_id: "app_id"
  google_app_secret: "secret"

test:
  google_app_id: "app_id"
  google_app_secret: "secret"

production:
  google_app_id: "app_id"
  google_app_secret: "secret"
```