This commit includes:
1. Adds fedora-messaging and happinesspacket-schema as a dependency in `base.py`
2. Sets env variable to fedora-messaging config file in `Dockerfile`
3. Adds `config.toml` [configuration file for fedora-messaging] to project's
app directory
4. Instructions to build a container for RabbitMQ in `docker-compose.yml`
5. Adds `happinesspacket_schema_package` which houses the schema and tests.
6. Configured MessageSenderConfirmationView to post messages to the broker.
