add RELEASING.md (googleapis#160)

jeanbza · web-flow · commit 357c62f0e4bb · 2019-04-25T09:56:59.000-06:00
diff --git a/RELEASING.md b/RELEASING.md
@@ -0,0 +1,4 @@
+# Releasing
+
+This repository does not have releases, since HEAD is always the correct commit
+to use. Similarly, we rely on semver pseudo-versions in dependor go.mods.
