QmlJS: Add 'reset code model' action.

Having to restart Creator should be a thing of the past.

Task-number: QTCREATORBUG-4813
Change-Id: Ide242ee299b5d34aecba4823032e27741dde4a86
Reviewed-on: http://codereview.qt.nokia.com/668
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@nokia.com>

src/plugins/qmljstools/qmljsmodelmanager.h

@@ -88,6 +88,9 @@ public:
     virtual CppQmlTypeHash cppQmlTypes() const;
     virtual BuiltinPackagesHash builtinPackages() const;
 
+public slots:
+    virtual void resetCodeModel();
+
 Q_SIGNALS:
     void projectPathChanged(const QString &projectPath);