Don't freak out if trying to close a socket that was already closed.

lib/roles/reaper.js

@@ -49,6 +49,10 @@ module.exports = function(options) {
 
   lifecycle.observe(function() {
     clearTimeout(timer)
-    push.close()
+
+    try {
+      push.close()
+    }
+    catch (err) {}
   })
 }