Squashed 'libraries/rsd/libraries/glxw/' content from commit 7ee2036

git-subtree-dir: libraries/rsd/libraries/glxw
git-subtree-split: 7ee20366357d9f7f9a73df7503710a87b8b93c41
Merge commit 'f9dde0b33d2b6d1c3cbf8685496cac5dd0c191f8' as 'libraries/rsd/libraries/glxw'
Add glxw to rsd.
Use glxw to run a compute shader.