Cherry-pick elastic#9767 to 6.5: Introduce next Changelog file (elast…

…ic#9807)

* Introduce next Changelog file (elastic#9767)

This introduces CHANGELOG.next.asciidoc and
CHANGELOG-developer.next.asciidoc. These changelog files will document
yet unreleased changes.

Having a separate changelog file reduces the work required to cleanup
the changelog, as rebasing and cherry-picking on backports sometimes
moves changelog entries into the wrong place.

(cherry picked from commit eae3bff)

* Adapt changelog to 6.5 branch

CHANGELOG-developer.next.asciidoc

@@ -0,0 +1,25 @@
+// Use these for links to issue and pulls. Note issues and pulls redirect one to
+// each other on Github, so don't worry too much on using the right prefix.
+:issue: https://github.com/elastic/beats/issues/
+:pull: https://github.com/elastic/beats/pull/
+
+This changelog is intended for community Beat developers. It covers the major
+breaking changes to the internal APIs in the official Beats and changes related
+to developing a Beat like code generators or `fields.yml`. Only the major
+changes will be covered in this changelog that are expected to affect community
+developers. Each breaking change added here should have an explanation on how
+other Beats should be migrated.
+
+Note: This changelog documents the current changes which are not yet present in
+an actual release.
+
+=== Beats version HEAD
+https://github.com/elastic/beats/compare/6.5.4..6.5[Check the HEAD diff]
+
+The list below covers the major changes between 6.5.4 and 6.5.5 only.
+
+==== Breaking changes
+
+==== Bugfixes
+
+==== Added

CHANGELOG.next.asciidoc

@@ -0,0 +1,90 @@
+// Use these for links to issue and pulls. Note issues and pulls redirect one to
+// each other on Github, so don't worry too much on using the right prefix.
+:issue: https://github.com/elastic/beats/issues/
+:pull: https://github.com/elastic/beats/pull/
+
+=== Beats version HEAD
+https://github.com/elastic/beats/compare/v6.5.4...6.5[Check the HEAD diff]
+
+==== Breaking changes
+
+*Affecting all Beats*
+
+*Auditbeat*
+
+*Filebeat*
+
+*Heartbeat*
+
+*Journalbeat*
+
+*Metricbeat*
+
+*Packetbeat*
+
+*Winlogbeat*
+
+*Functionbeat*
+
+- The CLI will now log CloudFormation Stack events. {issue}8912[8912]
+
+==== Bugfixes
+
+*Affecting all Beats*
+
+*Auditbeat*
+
+*Filebeat*
+
+*Heartbeat*
+
+*Journalbeat*
+
+*Metricbeat*
+
+*Packetbeat*
+
+*Winlogbeat*
+
+*Functionbeat*
+
+==== Added
+
+*Affecting all Beats*
+
+*Auditbeat*
+
+*Filebeat*
+
+*Heartbeat*
+
+*Journalbeat*
+
+*Metricbeat*
+
+*Packetbeat*
+
+*Winlogbeat*
+
+*Heartbeat*
+
+*Functionbeat*
+
+==== Deprecated
+
+*Affecting all Beats*
+
+*Filebeat*
+
+*Heartbeat*
+
+*Journalbeat*
+
+*Packetbeat*
+
+*Winlogbeat*
+
+*Functionbeat*
+
+==== Known Issue
+

docs/devguide/contributing.asciidoc

@@ -27,7 +27,7 @@ You only need to sign the CLA once.
 https://help.github.com/articles/using-pull-requests[submit a pull request]. In
 the pull request, describe what your changes do and mention any bugs/issues
 related to the pull request. Please also add a changelog entry to
-https://github.com/elastic/beats/blob/master/CHANGELOG.asciidoc[CHANGELOG.asciidoc].
+https://github.com/elastic/beats/blob/master/CHANGELOG.next.asciidoc[CHANGELOG.next.asciidoc].
 
 [float]
 [[adding-new-beat]]
@@ -147,4 +147,4 @@ In most cases `govendor fetch your/dependency@version +out` will get the job don
 
 To keep up to date with changes to the official Beats for community developers,
 follow the developer changelog
-https://github.com/elastic/beats/blob/master/CHANGELOG-developer.asciidoc[here].
+https://github.com/elastic/beats/blob/master/CHANGELOG-developer.next.asciidoc[here].