allocate application on heap instead of stack and delete it

This prevents problems with Vulkan debug layers that don't like
Vulkan calls to happen during C++ app shutdown.

Samples/Template_Linux/main.cpp

@@ -1,10 +1,11 @@
 #include "WickedEngine.h"
 #include <SDL2/SDL.h>
 
-wi::Application application;
+wi::Application* application;
 
 int main(int argc, char *argv[])
 {
+	application = new wi::Application();
 	// SDL window setup:
     sdl2::sdlsystem_ptr_t system = sdl2::make_sdlsystem(SDL_INIT_EVERYTHING | SDL_INIT_EVENTS);
     sdl2::window_ptr_t window = sdl2::make_window(
@@ -16,22 +17,22 @@ int main(int argc, char *argv[])
     SDL_Event event;
 
 	// set SDL window to engine:
-    application.SetWindow(window.get());
+    application->SetWindow(window.get());
 
 	// process command line string:
 	wi::arguments::Parse(argc, argv);
 
 	// just show some basic info:
-    application.infoDisplay.active = true;
-    application.infoDisplay.watermark = true;
-    application.infoDisplay.resolution = true;
-    application.infoDisplay.fpsinfo = true;
+    application->infoDisplay.active = true;
+    application->infoDisplay.watermark = true;
+    application->infoDisplay.resolution = true;
+    application->infoDisplay.fpsinfo = true;
 
 	bool quit = false;
 	while (!quit)
 	{
 		SDL_PumpEvents();
-		application.Run();
+		application->Run();
 
 		SDL_Event event;
 		while (SDL_PollEvent(&event))
@@ -48,7 +49,7 @@ int main(int argc, char *argv[])
 					quit = true;
 					break;
 				case SDL_WINDOWEVENT_RESIZED:
-					application.SetWindow(application.window);
+					application->SetWindow(application->window);
 					break;
 				default:
 					break;
@@ -62,6 +63,10 @@ int main(int argc, char *argv[])
 
 	wi::jobsystem::ShutDown(); // waits for jobs to finish before shutdown
 
+    // explicitly deleting prevents issues with Vulkan debug layers (debugdevice)
+    // which don't like vulkan calls happening during C++ application shutdown
+    delete application;
+
     SDL_Quit();
 
     return 0;