Notifications-python-client

Changed
* Using version 2 of the notification-api.
* When creating a new NotificationsAPIClient the optional parameter of service_id has been removed. The api_key is a combined string contain the api_key and the service_id
* Update to `NotificationsAPIClient.send_sms_notification()`:
* added `reference`: an optional unique identifier for the notification or an identifier for a batch of notifications. `reference` can be omitted.
* the `dict` returned has changed, learn more from the [README](https://github.com/alphagov/notifications-python-client#text-message).
* Update to `NotificationClient.send_email_notification()`:
* added `reference`: an optional unique identifier for the notification or an identifier for a batch of notifications. `reference` can be omitted.
* the `dict` returned has changed, learn more from the [README](https://github.com/alphagov/notifications-python-client#email).
* Update to the response of `NotificationsAPIClient.get_notification_by_id(id)`, see the [README](https://github.com/alphagov/notifications-python-client#get-the-status-of-one-message) for details.

Changed
* `BaseClient` method signature: `base_url` is now optional. See [41](https://github.com/alphagov/notifications-python-client/pull/41)
* `BaseClient` method signature: `api_key` is now a positional argument. See [41](https://github.com/alphagov/notifications-python-client/pull/41)

Changed
* Replace asserts with proper exceptions in jwt token code. See [40](https://github.com/alphagov/notifications-python-client/pull/40)

Prior versions

Changelog not recorded - please see pull requests on github.