fixes #156 Single Error/Success function? - add "done" and "complete"

lib/emitters/custom-event-emitter.js

@@ -33,6 +33,14 @@ module.exports = (function() {
     return this
     return this
   }
   }
 
 
+  CustomEventEmitter.prototype.done =
+  CustomEventEmitter.prototype.complete =
+  function(fct) {
+    this.on('failure', function(d){ fct(d, null) })
+        .on('success', function(d){ fct(null, d) })
+    return this
+  }
+
 
 
   return CustomEventEmitter
   return CustomEventEmitter
 })()
 })()