fixes deferred object to allow for async check along with validation

Author: orenf

src/defaults.js

@@ -100,7 +100,7 @@ var defaults = $.fn.steps.defaults = {
     stepsOrientation: stepsOrientation.horizontal,
 
     /*
-     * Tempplates
+     * Templates
      */
 
     /**

src/privates.js

@@ -440,25 +440,30 @@ function goToStep(wizard, options, state, index)
     }
 
     var oldIndex = state.currentIndex;
-    if (wizard.triggerHandler("stepChanging", [state.currentIndex, index]))
-    {
-        // Save new state
-        state.currentIndex = index;
-        saveCurrentStateToCookie(wizard, options, state);
-
-        // Change visualisation
-        refreshStepNavigation(wizard, options, state, oldIndex);
-        refreshPagination(wizard, options, state);
-        loadAsyncContent(wizard, options, state);
-        startTransitionEffect(wizard, options, state, index, oldIndex, function()
-        {
+    // 
+    var ajax = wizard.triggerHandler("stepChanging", [state.currentIndex, index]);
+
+    jQuery.when(ajax)
+      .done(function(status) {
+        if (status !== false) {
+          // Save new state
+          state.currentIndex = index;
+          saveCurrentStateToCookie(wizard, options, state);
+
+          // Change visualisation
+          refreshStepNavigation(wizard, options, state, oldIndex);
+          refreshPagination(wizard, options, state);
+          loadAsyncContent(wizard, options, state);
+          startTransitionEffect(wizard, options, state, index, oldIndex, function() {
             wizard.triggerHandler("stepChanged", [index, oldIndex]);
-        });
-    }
-    else
-    {
+          });
+        } else {
+          wizard.find(".steps li").eq(oldIndex).addClass("error");
+        }
+      })
+      .fail(function() {
         wizard.find(".steps li").eq(oldIndex).addClass("error");
-    }
+       });
 
     return true;
 }