Add RELEASE.md doc.

I always forget the cmdlines for tagging releases.

Bug: None
Test: Renders in Markdown.

Change-Id: I1a9f551ea5a31f66c46be8c3f9bc7e12160bb322
diff --git a/RELEASE.md b/RELEASE.md
new file mode 100644
index 0000000..30e4d58
--- /dev/null
+++ b/RELEASE.md
@@ -0,0 +1,15 @@
+# Tagging Minijail releases
+
+* Choose a new-ish, stable-ish commit (i.e. not one that implements a completely
+new feature).
+
+* Find the latest tag:
+`minijail$ git tag -l "linux-v*"`
+
+* Tag the commit with the next version number:
+`minijail$ git tag -a linux-v<N+1> <commit>`
+
+* Push the tag:
+`minijail$ git push aosp linux-v<N+1>`
+
+We will tag a new release ~monthly at the beginning of the month.