ui: Indexing UI

* Added DialogView with QtDialogView implementation to handle information dialogs
* Implemented QtIndexingDialog class that covers all different dialogs for indexing
* Directly communicate with DialogView from Prpject and all Tasks involved in indexing
* Block QtMainWindow UI while indexing

src/lib/CxxProject.h

@@ -16,7 +16,11 @@ protected:
 	virtual const std::shared_ptr<ProjectSettings> getProjectSettings() const;
 
 private:
-	CxxProject(std::shared_ptr<CxxProjectSettings> projectSettings, StorageAccessProxy* storageAccessProxy);
+	CxxProject(
+		std::shared_ptr<CxxProjectSettings> projectSettings,
+		StorageAccessProxy* storageAccessProxy,
+		DialogView* dialogView
+	);
 	CxxProject(const CxxProject&);
 
 	virtual bool allowsRefresh();