Add borderless window mode (from tasks) (#630)

src/io/settings_io.cpp

@@ -49,8 +49,8 @@ SettingsHandler::SettingsHandler(EngineSettings& settings) {
     builder.add("height", &settings.display.height);
     builder.add("samples", &settings.display.samples);
     builder.add("framerate", &settings.display.framerate);
-    builder.add("fullscreen", &settings.display.fullscreen);
     builder.add("limit-fps-iconified", &settings.display.limitFpsIconified);
+    builder.add("window-mode", &settings.display.windowMode);
 
     builder.section("camera");
     builder.add("sensitivity", &settings.camera.sensitivity);