Using Duo for per-SP-opt-in

[Cantor, Scott]

> I've documented in the wiki how to replicate the old Shib2 behavior
> without using the entire ECB configuration:
> 
>    https://wiki.shibboleth.net/confluence/x/ZABlAQ
> 
> ... if anyone sees errors in that article, feel free to correct them
> directly :)

I'm working with Duo soon so I'll certainly take a look.

> NB: also thanks to UChicago for sponsoring that work with Unicon. It's a
> much cleaner solution (IMO) than the Duo LoginHandler hook.

Any particular examples? Just curious, I haven't evaluated them yet for comparison.

-- Scott