Nýtt branch og kóðar plús breytingar á fyrri kóðum fyrir part 4

include/p_controller.h

@@ -11,6 +11,16 @@ public:
     virtual ~P_controller() {}
     virtual double update(double ref, double actual);
     virtual void reset() {}
+
+    virtual void set_Kp(double value)
+    {
+        Kp = value;
+    }
+
+    virtual void set_Ti(double value)
+    {
+        // P controller does not use Ti
+    }
 };
 
 #endif