v1.10.10-adapted

Adjustments

- Add run_ds, run_ds_nodash, run_ts, and run_date to task context
- Switch DAG processors to log to the scheduler stdout/stderr rather than
  separate files
- Fix a performance regression that caused finding DAG leaves to be an
  O(n^2) operation which takes very long for large DAGs

1.8.2rc4-adapted

Adjustments

- Add ProxyFix so Airflow works correctly behind ELB with SSL
- Disable Admin > Connections page which shows S3 access keys in plain
  text
- Disable unauthenticated trigger_dag API
  (api/experimental/dags/DAG_NAME/dag_runs)