Ray tracing samples can now also use the UI overlay

General cleanup, changed default settings.overlay value

examples/descriptorindexing/descriptorindexing.cpp

@@ -48,7 +48,6 @@ public:
 	VulkanExample() : VulkanExampleBase(ENABLE_VALIDATION)
 	{
 		title = "Descriptor indexing";
-		settings.overlay = true;
 		camera.type = Camera::CameraType::lookat;
 		camera.setPosition(glm::vec3(0.0f, 0.0f, -10.0f));
 		camera.setRotation(glm::vec3(-35.0f, 0.0f, 0.0f));