Initial commit of per route auth.

Added a new exception for flow control (evil!) that allows a method that's
executed inside a route to immediately return a response, rather than
relying on the executing route checking for a return value. It's horrible
to use an Exception for flow control, but in the auth scenario it is
representing a "failure" of sorts, and it gives us nice syntax, so nerrr
;-)
Refactor
Wired up per route claims methods
Added per route auth module to the forms auth demo project
Test fixup
Added optional reason and logging to the exception
Refactor of the tracelog to remove conditional during logging
Added reason to the security methods for early exit logging
Merge pull request #1137 from grumpydev/PerRouteAuth

Per route auth