Allows start RESTAS inside of cl-async's evet-loop.
Sample: 

(restas:add-toplevel-module '#:restas.demo nil 8080)

(setf wookie:*state* (restas.wookie:init-wookie-state))

(setf restas.wookie:*listener* (make-instance 'wookie:listener :port 8080))

(as:with-event-loop ()
  (wookie:start-server restas.wookie:*listener*))