[DOCS] Add X-Pack release notes to Elasticsearch Reference (elastic/x-pack-elasticsearch#2642)

* [DOCS] Add X-Pack release notes to Elasticsearch Reference

* [DOCS] Added X-Pack release note links

Original commit: elastic/x-pack-elasticsearch@2c2561cb6c

docs/en/index.asciidoc

@@ -17,6 +17,9 @@ include::setup-xes.asciidoc[]
 :edit_url:
 include::{es-repo-dir}/reference/index-shared2.asciidoc[]
 
+:edit_url!:
+include::release-notes/breaking-changes-xpack.asciidoc[]
+
 :edit_url:
 include::{es-repo-dir}/reference/index-shared3.asciidoc[]
 
@@ -29,5 +32,8 @@ include::commands/index.asciidoc[]
 :edit_url:
 include::{es-repo-dir}/reference/index-shared4.asciidoc[]
 
+:edit_url!:
+include::release-notes/xpack.asciidoc[]
+
 :edit_url:
 include::{es-repo-dir}/reference/index-shared5.asciidoc[]

docs/en/release-notes/7.0.0-alpha1.asciidoc

@@ -0,0 +1,15 @@
+[[xes-7.0.0-alpha1]]
+== {es} {xpack} 7.0.0-alpha1 Release Notes
+
+[float]
+[[xes-breaking-7.0.0-alpha1]]
+=== Breaking Changes
+
+Machine Learning::
+* The `max_running_jobs` node property is removed in this release. Use the
+`xpack.ml.max_open_jobs` setting instead. For more information, see <<ml-settings>>.
+
+See also:
+
+* <<release-notes-7.0.0-alpha1,{es} 7.0.0-alpha1 Release Notes>>
+* {logstash-ref}/xls-7.0.0-alpha1.html[Logstash {xpack} 7.0.0-alpha1 Release Notes]

docs/en/release-notes/breaking-changes-xpack.asciidoc

@@ -0,0 +1,31 @@
+[role="xpack"]
+[[breaking-changes-xes]]
+= {xpack} Breaking Changes
+
+[partintro]
+--
+This section summarizes the changes that you need to be aware of when migrating
+your application from one version of {xpack} to another.
+
+* <<breaking-7.0.0-xes>>
+
+See also:
+
+* <<breaking-changes,{es} Breaking Changes>>
+* {kibana-ref}/breaking-changes-xpackkb.html[{kib} {xpack} Breaking Changes]
+* {logstash-ref}/breaking-changes-xls.html[Logstash {xpack} Breaking Changes]
+
+--
+
+[role="xpack"]
+[[breaking-7.0.0-xes]]
+== {xpack} Breaking changes in 7.0.0
+
+
+Machine Learning::
+* The `max_running_jobs` node property is removed in this release. Use the
+`xpack.ml.max_open_jobs` setting instead. For more information, <<ml-settings>>.
+
+See also:
+
+* <<breaking-changes-7.0,{es} Breaking Changes>>

docs/en/release-notes/xpack.asciidoc

@@ -0,0 +1,20 @@
+[role="xpack"]
+[[release-notes-xes]]
+= {xpack} Release Notes
+
+[partintro]
+--
+This section summarizes the changes in each release for all of the {xpack}
+components in {es}.
+
+* <<xes-7.0.0-alpha1>>
+
+See also:
+
+* <<es-release-notes,{es} Release Notes>>
+* {kibana-ref}/release-notes-xpackkb.html[{kib} {xpack} Release Notes]
+* {logstash-ref}/release-notes-xls.html[Logstash {xpack} Release Notes]
+
+--
+
+include::7.0.0-alpha1.asciidoc[]