IdP authentication method selection

[Cantor, Scott]

> Looks like 492 : AuthenticationEngine.java, the <String, LoginHandler>
> HashMap returns an entrySet iterator, whose order is
> non-deterministic, but really not random, meaning no attempt was made
> to ensure randomness, afaict.
> 
> I think the wiki might be a little misleading by using the word "random".

Unspecified is probably the more precise term, yes.

-- Scott