exit-process! does not always exit the process, but throws an exception instead

I'll try to put up a pull request shortly.

```
diff --git a/storm-core/src/clj/backtype/storm/util.clj b/storm-core/src/clj/backtype/storm/util.clj
index 7bd4991..398584f 100644
— a/storm-core/src/clj/backtype/storm/util.clj
+++ b/storm-core/src/clj/backtype/storm/util.clj
@@ -316,7 +316,7 @@

(defn exit-process!
[val & msg]

• (log-error (RuntimeException. msg) "Halting process: " msg)
  + (log-error (RuntimeException. (str msg)) "Halting process: " msg)
  (.exit (Runtime/getRuntime) val))
  ```