Implement user defined runtime zoom factor

Add a mechanism to apply a custom zoom factor for the runtime window.
The desired zoom factor can be set in settings.ini as:
org.csstudio.display.builder.runtime.app/default_zoom_factor=1.23

Author: UrbanBobek

app/display/runtime/src/main/java/org/csstudio/display/builder/runtime/app/ZoomAction.java

@@ -8,6 +8,9 @@
 package org.csstudio.display.builder.runtime.app;
 
 import org.csstudio.display.builder.representation.javafx.JFXRepresentation;
+import org.phoebus.framework.preferences.AnnotatedPreferences;
+import org.phoebus.framework.preferences.PreferencesReader;
+import org.phoebus.framework.preferences.Preference;
 
 import javafx.application.Platform;
 import javafx.scene.control.ComboBox;
@@ -19,20 +22,33 @@ public class ZoomAction extends ComboBox<String>
 {
     private boolean updating = false;
 
+    @Preference public static double default_zoom_factor;
+
+    static
+    {
+        AnnotatedPreferences.initialize(ZoomAction.class, "/zoom_preferences.properties");
+    }
+
     /** @param instance {@link DisplayRuntimeInstance} */
     public ZoomAction(final DisplayRuntimeInstance instance)
     {
         setEditable(true);
         setPrefWidth(100.0);
         getItems().addAll(JFXRepresentation.ZOOM_LEVELS);
-        setValue(JFXRepresentation.DEFAULT_ZOOM_LEVEL);
         // For Ctrl-Wheel zoom gesture
         instance.getRepresentation().setZoomListener(txt ->
         {
             getSelectionModel().clearSelection();
             getEditor().setText(txt);
         });
         setOnAction(event -> zoom(instance.getRepresentation()));
+
+        // Add the zoom action into a queue
+        Platform.runLater(() ->
+        {
+            String zoom = String.format("%d %%", (int)(default_zoom_factor * 100));
+            setValue(zoom);
+        });
     }
 
     private void zoom(final JFXRepresentation representation)

app/display/runtime/src/main/resources/zoom_preferences.properties

@@ -0,0 +1,6 @@
+# ----------------------
+# Package org.csstudio.display.builder.runtime.app
+# ----------------------
+
+# Defualt zoom factor(double) of display runtime window
+default_zoom_factor=1.00