Reduce complexity in the webserver by using channels.
Add stuglasers pychan library to get go-like channel suppport.
Use channels in terminalio and simplify the implementation a bit.
Use channels to implement the terminal and iframe request handlers.
Prepare for using core.asnyc.
Allow running a simple debug client.

Next: extend the debug client and fit the old js-string-eval API into the
clojurescript client message API.