Ensuring content manager is flushed after creating user

Hi,

I've made a small change to flush the content manager / session after the user is created.
This ensures that the user can be queried by other subsequent callers (e.g. authentication service).   

I also removed the_attemptedToSaveUser field check - it's not needed if the user can now be queried in the same request.

Please review/test and let me know if there are any issues :)