Disable BigScreen by default

src/org/kde/kdeconnect/Plugins/BigscreenPlugin/BigscreenPlugin.java

@@ -56,6 +56,11 @@ public class BigscreenPlugin extends Plugin {
         return ContextCompat.getDrawable(context, R.drawable.ic_presenter);
     }
 
+    @Override
+    public boolean isEnabledByDefault() {
+        return false;
+    }
+
     @Override
     public boolean hasSettings() {
         return false;