This might turn into a complete wire protocol with special
client software. For now it will be a simple client interface
that you can use with telnet to do certain things.
This is using flex to implement the parsing. Implementation
and more commands will follow.
One can use add_timer or schedule_timer to add a timer. After
the timeout time has been reached the callback will be called.
One can call add_time/schedule_timer and del_timer from within
the callback.