D3D12 - Add support for memory allocators

[kingofthebongo2008]

CreateComittedResource is fine,

However is good to add interface to CreateTexture, CreateTextureEx

Particularly on d3d12 this allocator is very often used

https://github.com/GPUOpen-LibrariesAndSDKs/D3D12MemoryAllocator

Support for a callback to the interface + initial resource transition will be fine