Ray Tracing In Vulkan Release 4

• Upgraded to latest Vulkan SDK (1.1.121).
• Upgraded to vcpkg 2019.09.
• Added texture support (the renderer is a bit slower now, as I do not specialise the shaders based on the scene).
• Added new scene to show texture support.
• Added support for benchmarking all scenes in one command line.
• Added framebuffer size to statistic UI (it does not always match what you requested).
• Fixed light scattering through opaque back faces.