Runtime error work done

[Cantor, Scott]

I believe I've got this locked down after considerable experimentation 
now, so Marvin, you probably will want to propagate that into the CAS 
flows.

The subflows now return a RuntimeException event when it happens, so you 
can route on that, and do it at the top level similarly to the way the 
SAML abstract flow is doing it, to ensure anything caught is also logged.

-- Scott