Misc updates related to release.

howto/release/components/index.rst
howto/release/components/maclearner/index.rst
howto/release/components/olttopology/index.rst
howto/release/components/pppoeagent/index.rst
----------------------------------------------
  o Document maven plugins and dependencies for components.

config.mk
---------
  o Disable yaml linting for now, volume problems to cleanup.

howto/code/index.rst
howto/code/job-failures.rst
---------------------------
  o Added a new page for documenting common jenkins problems.

howto/release/checklist.rst
howto/release/preparation.rst
overview/contributing.rst
release_notes/release_process.rst
---------------------------------
  o Incremental edits related to release steps.

Change-Id: I84db4d422556dbbeeaa5bf5351060dc193585e40
diff --git a/howto/code/index.rst b/howto/code/index.rst
index 0d23582..685dc2a 100644
--- a/howto/code/index.rst
+++ b/howto/code/index.rst
@@ -4,5 +4,6 @@
 .. toctree::
    :maxdepth: 2
 
+   job-failures
    linting
    pull_request
diff --git a/howto/code/job-failures.rst b/howto/code/job-failures.rst
new file mode 100644
index 0000000..ac7870b
--- /dev/null
+++ b/howto/code/job-failures.rst
@@ -0,0 +1,42 @@
+Jenkins: Common job failures
+============================
+
+ERROR: Duplicate tag  (job: version-tag_wildcard)
+-------------------------------------------------
+
+.. code:: bash
+
+   02:44:55 v4.3.3   Tagged by CORD Jenkins version-tag job: 384, for Gerrit patchset: 33916
+   02:44:55 v4.3.4   Tagged by CORD Jenkins version-tag job: 388, for Gerrit patchset: 34359
+   02:44:55 go-based project found, using v-prefixed version for git tags: v4.3.4
+   02:44:55 Version string '4.3.4' in 'VERSION' is a SemVer released version!
+   02:44:55 ERROR: Duplicate tag: v4.3.4
+   02:44:55 Build step 'Execute shell' marked build as failure
+
+FIX:
+^^^^
+
+Most VOLTHA repositories contain the file `VERISON <https://gerrit.opencord.org/plugins/gitiles/voltha-openolt-adapter/+/refs/heads/master/VERSION>`_ which contain a semantic version string for builds.
+
+Content and use of the VERSION file is documented [`here <https://docs.voltha.org/master/overview/contributing.html#versioning>`_]
+
+- Problem #1: No VERSION file included with a patch.
+
+  - If a VERSION file was not included in your patch simply add it with an incremented version string.
+
+- Problem #2: Development collision
+
+  - Periodically two devs may work in a repository at the same time.
+  - Jenkins job processing is on a first-come-first-serve-basis.
+  - When two patches are submitted for inclusion
+
+    - The first patch will be accepted.
+    - The second patch will fail with a duplicate tag.
+
+  - This is a normal development event, when it happens check the repository
+    to determine the latest VERSION string, increment the value and include
+    the VERSION file in your patch.
+  - ie: git commit --amend; git rebase; git review
+
+
+
diff --git a/howto/release/checklist.rst b/howto/release/checklist.rst
index 66cd045..789d779 100644
--- a/howto/release/checklist.rst
+++ b/howto/release/checklist.rst
@@ -113,3 +113,5 @@
      - Run gofmt on sources
    * - make mod-update
      - Update go mod files
+
+Review `voltha-helm-charts <https://gerrit.opencord.org/plugins/gitiles/voltha-helm-charts>`_
diff --git a/howto/release/components/index.rst b/howto/release/components/index.rst
index b46cd67..3d4dfdb 100644
--- a/howto/release/components/index.rst
+++ b/howto/release/components/index.rst
@@ -15,3 +15,13 @@
    voltha-openolt-adapter
    voltha-openonu-adapter-go
 
+   maclearner/index
+   mcast/index
+   olt/index
+   olttopology/index
+   pppoeagent/index
+
+
+See Also
+--------
+   `VOLTHA and ONOS update procedures <https://docs.voltha.org/master/operations/software-upgrade.html?highlight=set%20global%20image>`_.
diff --git a/howto/release/components/maclearner/index.rst b/howto/release/components/maclearner/index.rst
new file mode 100644
index 0000000..5020439
--- /dev/null
+++ b/howto/release/components/maclearner/index.rst
@@ -0,0 +1,13 @@
+ONOS Component: maclearner
+==========================
+
+Dependencies (pom.xml)
+----------------------
+
+- Maven Plugins
+
+- Components
+
+`gerrit:mac-learning <https://gerrit.opencord.org/plugins/gitiles/mac-learning/+/refs/tags/1.2.1>`_
+`maven central:maclearner <https://central.sonatype.com/artifact/org.opencord/maclearner/1.2.1>`_
+pom.xml:maclearner
diff --git a/howto/release/components/olttopology/index.rst b/howto/release/components/olttopology/index.rst
new file mode 100644
index 0000000..3394cd1
--- /dev/null
+++ b/howto/release/components/olttopology/index.rst
@@ -0,0 +1,14 @@
+ONOS Component: olttopology
+===========================
+
+Dependencies (pom.xml)
+----------------------
+
+- Maven Plugins
+
+  - spotbugs-maven-plugin
+  - findsecbugs-plugin
+
+- Components
+
+  - sadis
diff --git a/howto/release/components/pppoeagent/index.rst b/howto/release/components/pppoeagent/index.rst
new file mode 100644
index 0000000..9e81c46
--- /dev/null
+++ b/howto/release/components/pppoeagent/index.rst
@@ -0,0 +1,14 @@
+ONOS Component: pppoeagent
+==========================
+
+Dependencies (pom.xml)
+----------------------
+
+- Maven Plugins
+
+  - spotbugs-maven-plugin
+  - findsecbugs-plugin
+
+- Components
+
+  - sadis
diff --git a/howto/release/preparation.rst b/howto/release/preparation.rst
index a46d385..2c515d0 100644
--- a/howto/release/preparation.rst
+++ b/howto/release/preparation.rst
@@ -11,7 +11,7 @@
 
 Confluence
 ----------
-Create a `release tracking page` <https://wiki.opennetworking.org/display/VOLTHA/v2.12>`_ in confluence, there are a lot of details
+Create a `release tracking page <https://wiki.opennetworking.org/display/VOLTHA/v2.12>`_ in confluence, there are a lot of details
 
 - Jira tickets related to release and VOLTHA builds.
 - Jenkins jobs: state, failures and tickets.
@@ -19,7 +19,7 @@
 
 docs.voltha.org
 ---------------
-- Create a stub `release notes <https://docs.voltha.org/master/release_notes/voltha_2.12.html>`_ page beneath `docs.voltha.org/release_notes <https://docs.voltha.org/master/release_notes/index.html>`_ (`HOWTO <https://docs.voltha.org/master/howto/release/release-notes.html>`_
+- Create a stub `release notes <https://docs.voltha.org/master/release_notes/voltha_2.12.html>`_ page beneath `docs.voltha.org/release_notes <https://docs.voltha.org/master/release_notes/index.html>`_ (`HOWTO <https://docs.voltha.org/master/howto/release/release-notes.html>`_)
 
 golang repositories
 -------------------