Squashed 'third_party/SPIRV-Headers/' content from commit 79b6681aa

git-subtree-dir: third_party/SPIRV-Headers
git-subtree-split: 79b6681aadcb53c27d1052e5f8a0e82a981dbf2f
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..9bcdd5a
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+build
+out