bugfix -- remove while, change to go-loop

In `src/probe/core.clj` you've got a `recur` at the tail position of a `while` loop:

```clojure
(defonce error-router
  (go
   (while true
     (when-let [{:keys [state exception]} (<! error-channel)]
       (clog/error "Probe error detected" state exception)
       (recur)))))
```

I get the feeling that this was supposed to be a `go-loop`.