dxgitrace: Fix UpdateSubresource's blob size calculation for non-null pDstBox.

The box dimensions where being incorrectly minified.
d3dretrace: Extend UpdateSubresource's special code to UpdateSubresource1.
dxgitrace: Try to detect non-overlapping buffer writes.

Work in progress.
dxgitrace: Shadow D3D11 buffers properly.
dxgitrace: Fill a pattern when discarding and shadowing.
dxgitrace: Ensure buffers are initialized.
dxgitrace: Use CRC32C hashes of 512byte blocks instead of memcopies.

Much faster.