Minor doc edits

howto/docs.voltha.org/quickstart.rst
  - Fixed code-block(::) statement for rendering.
  - Include sample text for commit message format.

Change-Id: I71d27b22e4ea50a327ed31932e4add166600e852
diff --git a/howto/release/index.rst b/howto/release/index.rst
index a75a588..6fa5f55 100644
--- a/howto/release/index.rst
+++ b/howto/release/index.rst
@@ -18,7 +18,6 @@
    charts/index
 
    bbsim/index
-
    voltctl/index
    voltctl/install
    voltctl/release