Wizards: Close wizards with escape

Since they are no longer modal, the "return to editor" shortcut was
executed for the escape key instead.

Change-Id: I4505f49105ad46f7c5f9e0257e77a8ca4652ef06
Reviewed-by: Daniel Teske <daniel.teske@digia.com>

src/libs/utils/wizard.h

@@ -72,6 +72,9 @@ signals:
     void nextClicked(); /* workaround for QWizard behavior where page->initialize is
                          * called before currentIdChanged */
 
+protected:
+    bool event(QEvent *event);
+
 private slots:
     void _q_currentPageChanged(int pageId);
     void _q_pageAdded(int pageId);