v1.10: Added CPU encoding

CPU encoding backend (--backend cpu)
Sampling change (mostly for LLVMpipe+anisotropic filtering)
Higher quality when the first texture in a set is grayscale

v1.06

Changed how the 2nd 1/4 resolution latent is sampled because on Intel GPU's LOD bias is applied differently vs. NVidia/AMD. Now using textureGrad(), which works on them all.

v1.05

Adding Vulkan sample, VK_NV_cooperative_vector.
Tested on AMD/NVidia.

v1.00

Initial release