Refactored model.update and destroy to use promises

lib/hooks.js

@@ -92,7 +92,9 @@ Hooks.runHooks = function() {
         if (!!arguments[0]) {
           return reject(arguments[0])
         } 
-        resolveArgs = Array.prototype.slice.call(arguments, 1)
+        if (arguments.length) {
+          resolveArgs = Array.prototype.slice.call(arguments, 1)
+        }
 
         return run(hooks[tick])
       }))
@@ -101,7 +103,9 @@ Hooks.runHooks = function() {
         maybePromise.spread(function () {
           tick++
 
-          resolveArgs = Array.prototype.slice.call(arguments)
+          if (arguments.length) {
+            resolveArgs = Array.prototype.slice.call(arguments)
+          }
 
           return run(hooks[tick])
         }, reject)