Subject c14n on initial AuthnRequest

[Cantor, Scott]

Also, I don't know exactly how your internals work, but I was fortunate that my internal username normalization matches the LHS of our email addresses. If they hadn't it would have required custom code and a custom flow to do the reverse mapping, essentially like the attribute-based post-login c14n flow does, and I might end up just building that, or a scripted variant, into 4.1.

-- Scott