* should PoCos explicitly reveal and discuss their session architecture
in documentation, and perhaps specify which callbacks are called in what
session context, and what heap variables are available to the callbacks?
* should there we ways to look to the event queues and see if any sessions have events
waiting to run future. This would have simplified the shutdown logic in the
TestServer component.
* Should the be standard ways for Pocos to give users ways to set up
handlers in nested sessions and to pass state data down to handlers?
* Should there be standard error and tracing procedures for POE? Maybe something
that runs with a console/ps type utility?