title: Airflow, enable dag on creation
body: <p>When I create a DAG with air flow in python I can pass some parameters.</p>
  
  <pre><code>SETTINGS = {
      'owner': 'hello',
      'depends_on_past': False,
      'start_date': datetime(2019, 1, 1),
      'email_on_failure': False,
      'email_on_retry': False,
      'retries': 1,
      'retry_delay': timedelta(minutes=5),
   }
  dag = DAG(dag_id,
                schedule_interval='@daily',
                catchup=False,
                default_args=SETTINGS)
  </code></pre>
  
  <p>Yet when I do so, I still have to go on the interface and to enable the DAG with a click. I would like to know if there is a settings to pass to do it directly on creation. I think it has something to do with "pause" but can't find the name of the parameter.</p>