Add an nginx service to group all http services on the same service endpoint

namely:

• http://localhost:5080/ -> web app
• http://localhost:5080/flower/ -> celery dashboard
• http://localhost:5080/rabbitmq/ -> amqp dashboard
• http://localhost:5080/scheduler/ -> swh-scheduler API
• http://localhost:5080/storage/ -> swh-storage API
• http://localhost:5080/indexer-storage/ -> swh-indexer-storage API
• http://localhost:5080/deposit/ -> swh-deposit API
• http://localhost:5080/objstorage/ -> swh-objstorage API