Fix replacement of variables in wizard parameters.

This was broken in case of no targets page being used, and using
the project name variable in default values for wizard parameters in the
page following the intro page (like it is done in the hello world
wizard).

Reviewed-by: Friedemann Kleint

src/libs/utils/wizard.h

@@ -57,6 +57,11 @@ public:
     void setStartId(int pageId);
 
     WizardProgress *wizardProgress() const;
+    virtual bool validateCurrentPage();
+
+signals:
+    void nextClicked(); /* workaround for QWizard behavior where page->initialize is
+                           called before currentIdChanged */
 
 private slots:
     void _q_currentPageChanged(int pageId);