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/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
 -------------------