2nd set of Hubble textures, 16k x 16k BC1 format

This "release" is actually a .zip containing a few textures (in .xet format) for use with Sampler Feedback Streaming. These are different images from the prior release, but also a different format (BC1 vs. BC7) which is half the file size for the same dimensions. Place these textures in the same directory as the other release. Note that these BC1 textures and the prior BC7 textures will all co-exist within the same D3D12 heap.

Recommended usage:

demo-hubble.bat -mediadir