Small changes + adding bark.swipe

### Small changes

* Renamed `default_settings` to `config`
* Remove `auth_token` from request JSON in the `BarkAuthenticatedApiEndpoint`
* Add `bark.lib.time` and `bark.lib.tests.BarkTestCase.auth_post()`

### Added Swipe

Not fully implemented, has some **TODO** items in it. Just laying the foundation.