Misc doc edits for release.

release_notes/voltha_2.12.rst
-----------------------------
  o Update version and URLs for kafka
  o Update version and URLs for olt

howto/release/tasks/index.rst
howto/release/tasks/golang_gofmt_syntax.rst
-------------------------------------------
  o Document std golang formatting with gofmt -s -e -w.
  o Document content with references (commit message, make lint)
    diff --git a/howto/release/tasks/index.rst b/

Include a few edits from gerrit id I6e9658c23f436f83d423f74e01b2966943d2fe08

Change-Id: I27ad46ddd6673a9e35e794b1d3e8bb0644e8260d
diff --git a/overview/release_process.rst b/overview/release_process.rst
index 3157f7c..5abf658 100644
--- a/overview/release_process.rst
+++ b/overview/release_process.rst
@@ -1,5 +1,6 @@
 VOLTHA Release process
 ======================
+
 This document describes the technical steps of VOLTHA's release process.
 The document assumes you are creating a release named voltha-X.Y, where X is the major release versio
 and the y is the minor.
diff --git a/overview/troubleshooting.rst b/overview/troubleshooting.rst
index 12404b4..1f08de9 100644
--- a/overview/troubleshooting.rst
+++ b/overview/troubleshooting.rst
@@ -36,7 +36,7 @@
 
 And then in wireshark select ``File -> Import from Hex Dump``
 
-Or you can decode a single packet using this online tool: `https://hpd.gasmi.net <https://hpd.gasmi.net>`_
+Or you can decode a single packet using this online tool: ``http://hpd.gasmi.net``.
 
 To get all the EAPOL packets: ``grep -e '888e' packets.trace``