Add discontinued Elasticsearch versions info to release notes and page

Fix the previously documented 3.1.x version in that Elasticsearch page.

Remove the 2.15.8 mention as the corresponding 2.15.x column has been
removed since.

Change-Id: Iba9a444f721dfe259daaa7001d5a713881c838ff
diff --git a/pages/site/elasticsearch.md b/pages/site/elasticsearch.md
index f8ad1fa..8b73775 100644
--- a/pages/site/elasticsearch.md
+++ b/pages/site/elasticsearch.md
@@ -10,11 +10,11 @@
 
 | Elasticsearch Version | 2.16.x  | 3.0.x | 3.1.x | Notes                                            |
 |-----------------------|---------|-------|-------|--------------------------------------------------|
-| 2.4.x                 |         |       |       | Support discontinued in 2.15.8, 2.16.1 and 3.0.0 |
-| 5.6.x                 |         | 3.0.0 | 3.1.0 | Support discontinued in 2.16.18, 3.0.9 and 3.1.6 |
-| 6.2.x                 |         | 3.0.0 | 3.1.0 |                                                  |
-| 6.3.x                 |         | 3.0.0 | 3.1.0 |                                                  |
-| 6.4.x                 | 2.16    | 3.0.0 | 3.1.0 |                                                  |
+| 2.4.x                 | 2.16    |       |       | Support discontinued in 2.16.1 and 3.0.0         |
+| 5.6.x                 | 2.16    | 3.0.0 | 3.1.0 | Support discontinued in 2.16.18, 3.0.9 and 3.1.5 |
+| 6.2.x                 | 2.16    | 3.0.0 | 3.1.0 | Support discontinued in 2.16.18, 3.0.9 and 3.1.5 |
+| 6.3.x                 | 2.16    | 3.0.0 | 3.1.0 | Support discontinued in 2.16.18, 3.0.9 and 3.1.5 |
+| 6.4.x                 | 2.16    | 3.0.0 | 3.1.0 | Support discontinued in 2.16.18, 3.0.9 and 3.1.5 |
 | 6.5.x                 | 2.16.1  | 3.0.0 | 3.1.0 |                                                  |
 | 6.6.x                 | 2.16.5  | 3.0.0 | 3.1.0 |                                                  |
 | 6.7.x                 | 2.16.8  | 3.0.0 | 3.1.0 |                                                  |
diff --git a/pages/site/releases/3.0.md b/pages/site/releases/3.0.md
index eb7ee84..c04d227 100644
--- a/pages/site/releases/3.0.md
+++ b/pages/site/releases/3.0.md
@@ -206,6 +206,9 @@
     [cache.enableDiskStatMetrics](http://gerrit-documentation.storage.googleapis.com/Documentation/2.16.18/config-gerrit.html#cache.enableDiskStatMetrics)
     configuration option.
 
+  * [Issue 12527](https://bugs.chromium.org/p/gerrit/issues/detail?id=12527):
+  Elasticsearch: Support for EOL versions v5.6 and v6.0 to v6.4 is discontinued
+
 ### 3.0.8
 
 * Breaking Changes
diff --git a/pages/site/releases/3.1.md b/pages/site/releases/3.1.md
index d7ed6aa..ebfebb3 100644
--- a/pages/site/releases/3.1.md
+++ b/pages/site/releases/3.1.md
@@ -306,6 +306,9 @@
     [cache.enableDiskStatMetrics](http://gerrit-documentation.storage.googleapis.com/Documentation/2.16.18/config-gerrit.html#cache.enableDiskStatMetrics)
     configuration option.
 
+  * [Issue 12527](https://bugs.chromium.org/p/gerrit/issues/detail?id=12527):
+  Elasticsearch: Support for EOL versions v5.6 and v6.0 to v6.4 is discontinued
+
 ### 3.1.4
 
 * Breaking Changes
diff --git a/pages/site/releases/3.2.md b/pages/site/releases/3.2.md
index 8b829c5..cf8d95b 100644
--- a/pages/site/releases/3.2.md
+++ b/pages/site/releases/3.2.md
@@ -72,6 +72,9 @@
 
 ### Breaking Changes
 
+* [Issue 12527](https://bugs.chromium.org/p/gerrit/issues/detail?id=12527):
+Elasticsearch: Support for EOL versions v5.6 and v6.0 to v6.4 is discontinued
+
 ## New Features
 
 ### File Uploads