[VOL-5009] - Update release notes

[VOL-5061]

overview/releases.rst
---------------------
  o Correct start/end release dates for v2.10-v2.12 to reflect reality.

release_notes/voltha_2.12.rst
-----------------------------
  o Populate the onos apps grid with versioned artifact and VCS urls.
  o Component kafka the only holdout

howto/release/checklist.rst
howto/release/components/index.rst
howto/release/index.rst
howto/release/voltha-docs/index.rst
howto/release/voltha-docs/release_notes.rst
howto/release/branching/
howto/release/components/igmpproxy/
howto/release/components/kafka/
howto/release/components/maclearner/
howto/release/components/pppoeagent/
howto/release/voltha-docs/release_history.rst
---------------------------------------------
  o Add more random content and links for release dependencies and tasks.

Change-Id: I31338488a4e626a97435429a36e200d54cf6267e
diff --git a/howto/release/components/index.rst b/howto/release/components/index.rst
index 3910d27..7001c48 100644
--- a/howto/release/components/index.rst
+++ b/howto/release/components/index.rst
@@ -4,6 +4,14 @@
 .. toctree::
    :maxdepth: 1
 
+   igmpproxy/index
+   kafka/index
+   maclearner/index
+   mcast/index
+   olt/index
+   olttopology/index
+   pppoeagent/index
+
    onos_components
    onos_dependencies
    maven_plugins
@@ -19,13 +27,6 @@
    atomix/index
    onos/index
 
-   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>`_.