Finish Vulkan + DirectX12 implementation (Graphics+)

[Nielsbishere]

• [ ] Layers for swapchain, render targets and depth stencil.
• [ ] Lazily allocated swapchain for MSAA https://docs.vulkan.org/spec/latest/proposals/proposals/VK_EXT_multisampled_render_to_single_sampled.html
• [ ] Look into pipeline cache again and determine if it's worth the overhead. Because some sources say that for NV/AMD is currently faster to let the driver handle it. However, mobile might be a different story.
• [ ] Cubemap and 3D texture support in RenderTexture and DeviceTexture
• [ ] Multi threading command list building
• [ ] Command buffer re-using (hashing commands and object versions) if they're the same
• [ ] Using copy queue for staging
• [ ] Factory system for the following: Sampler, Pipeline
• [ ] Render task system for building command list and maintaining render targets
• [x] Shader reflection system to know what extensions are required
• [ ] BLAS update/refit
• [ ] BLAS compact
• [ ] TLAS update/refit
• [ ] TLAS compact
• [ ] Ray trace indirect
• [ ] Adding async compute support
• [ ] Mesh shaders.
• [ ] Multi view.
• [ ] Ray motion blur.
• [ ] Ray micromap opacity.
• [ ] Ray micromap displacement.
• [ ] Variable rate shading.
• [ ] Render pass creation
• [ ] Video encode.
• [ ] Video decode.
• [ ] Arm can only do 2M vertices per renderpass. Make this a warning unless device vendor is arm. https://github.com/ARM-software/vulkan_best_practice_for_mobile_developers/blob/master/docs/memory_limits.md
• [ ] Allow swapchain to change present mode.
• [ ] batch vkUpdateDescriptorSets.
• [ ] Stream output
• [ ] Allow/validate binding ranges in primitive buffers.
• [ ] Allow transitioning ranges of buffers.
• [ ] Make staging buffer bigger if lots of dedicated staging buffers that are barely bigger than 10% of the staging buffer.
• [ ] Split barriers d3d12 & vkCmdSetEvent + vkCmdWaitEvents in vulkan: https://gamedev.net/forums/topic/676655-how-could-we-benefit-from-using-split-barriers/5279391/