[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/pppoeagent/index.rst b/howto/release/components/pppoeagent/index.rst
index 9e81c46..4de5f77 100644
--- a/howto/release/components/pppoeagent/index.rst
+++ b/howto/release/components/pppoeagent/index.rst
@@ -12,3 +12,15 @@
 - Components
 
   - sadis
+
+- Repository
+
+  `pppoeagent <https://gerrit.opencord.org/plugins/gitiles/pppoeagent>`_
+  `gerrit:122 <https://gerrit.opencord.org/plugins/gitiles/pppoeagent/+/refs/tags/1.2.2>`_
+  `github:122 <https://github.com/opencord/pppoeagent/tree/1.2.2>`_
+
+- `Maven Central <https://central.sonatype.com/search?q=pppoeagent>`_
+
+  - `pkg:121 <https://central.sonatype.com/artifact/org.opencord/pppoeagent/1.2.1>`_
+  - `api:121 <https://central.sonatype.com/artifact/org.opencord/pppoeagent-api/1.2.1>`_
+  - `app:121 <https://central.sonatype.com/artifact/org.opencord/pppoeagent-app/1.2.1>`_