GUI: serialization refactoring part 7

The the rest of classes have got readFrom and writeTo methods.

Serialization of instruments is done.

The rest of work is to remove all usages and mentions of serialization.

GUI/Model/Device/BeamAngleItems.h

@@ -22,7 +22,7 @@ public:
     BeamAzimuthalAngleItem();
 
     void serialize(Streamer& s) override;
-    void readFrom(QXmlStreamReader* r);
+    void readFrom(QXmlStreamReader* r) override;
 
     double azimuthalAngle() const;
     double scaleFactor() const override;
@@ -37,7 +37,7 @@ public:
     BeamInclinationAngleItem();
 
     void serialize(Streamer& s) override;
-    void readFrom(QXmlStreamReader* r);
+    void readFrom(QXmlStreamReader* r) override;
 
     double inclinationAngle() const;
     double scaleFactor() const override;