Squashed 'extern/snappy/snappy/' content from commit 1ff9be9

git-subtree-dir: extern/snappy/snappy
git-subtree-split: 1ff9be9b8fafc8528ca9e055646f5932aa5db9c4
Merge commit '3d8b9e671b365848eab1be6d11c9e39c52138eed' as 'extern/snappy/snappy'
[FOLD] Move snappy to extern, unity