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- Major update to support the Duo Universal Prompt by default
- Adding ``DUO_LEGACY_PROMPT`` setting to fallback to traditional behavior
- Traditional prompt should be considered deprecated and will be removed if Duo ever removes support for it.
- Optional ``FAIL_OPEN`` per-app setting for allowing Duo being unavailable or refusing to authenticate an insecure client to skip second factor
- Per-app settings ``IKEY``, ``SKEY``, and ``HOST``, may now be referred to as ``CLIENT_ID``, ``CLIENT_SECRET``, and ``API_HOSTNAME``, respectively
- ``AKEY`` is no longer used by Universal Prompt