ClassView: Modernize

modernize-use-nullptr
modernize-use-auto
modernize-use-override
modernize-use-equals-default
modernize-use-using
modernize-loop-convert

Change-Id: I7dcc03ad38f6f943bc4c8b1049e7069f4b99c985
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/classview/classviewmanager.h

@@ -42,9 +42,9 @@ class Manager : public QObject
     Q_OBJECT
 
 public:
-    explicit Manager(QObject *parent = 0);
+    explicit Manager(QObject *parent = nullptr);
 
-    virtual ~Manager();
+    ~Manager() override;
 
     //! Get an instance of Manager
     static Manager *instance();