QmlJS: Implement renaming of usages.

Task-number: QTCREATORBUG-3669
Change-Id: I2c600cae5ac445ca80eafe6557ba276c14a77a73
Reviewed-on: http://codereview.qt.nokia.com/1413
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@nokia.com>

src/plugins/qmljseditor/qmljseditor.h

@@ -168,6 +168,7 @@ public slots:
     void forceSemanticRehighlight();
     void followSymbolUnderCursor();
     void findUsages();
+    void renameUsages();
     void showContextPane();
     virtual void setFontSettings(const TextEditor::FontSettings &);