Resin-sdk

* Add `versionist.conf.js` config and prepare for VersionBot control. 58 [Heds Simons]

Added

- Add a timeout for all requests (defaults to 30 seconds).
- Add Build class to the docs.
- Add details about the old and new returned objects from old and new API.

Added

- Add support for Python 3.
- Implement base class for resin exceptions.

Changed

- Fix a bug in `resin.models.device.get_all_by_application()` to make it
works with API v3.

Added

- Implement `device.get_dashboard_url()` that return the Resin Dashboard URL for a specific device.
- Implement `device_os.get_config()` that retrieves an application config.json.
- Implement `application.enable_device_urls()` and `application.disable_device_urls()` that enable/disable the URL for all devices belong to an application.
- Implement methods at device and application level for granting and revoking support access.
- Implement `application.generate_provisioning_key()` that generates a device provisioning key for a specific application.

Changed

- Upgrade Pine endpoint to Resin API v3.
- Add validation for environment variable name.
- Update `device.register()`, device registration now uses provisioning key.

Changed

- Add additional API endpoints: `resin.models.application.enable_rolling_updates()`, `resin.models.application.disable_rolling_updates()`, `resin.models.device.get_all_by_application_id()` and `resin.models.device.set_to_build()` by [amirfuhrmann](https://github.com/amirfuhrmann)

Changed

- Fix issue with auth.is_logged_in() raises Unauthorized exception.