Howto release doc additions

code/release-bugfix.rst
-----------------------
  o Howto create a release branch patch

howto/release/overview.rst
--------------------------
  o Early writeup of release actions.
  o Edits needed for both branch=release and branch=master

Change-Id: I34ecc54217b2f185f7737f3244fceb2a4ddf4c5d
diff --git a/howto/code/index.rst b/howto/code/index.rst
index 9152cec..4639434 100644
--- a/howto/code/index.rst
+++ b/howto/code/index.rst
@@ -8,4 +8,5 @@
    job-failures
    linting
    pull_request
+   release-bugfix
    voltha-protos