docs: expand release notes and redirect "changes-in-repmgr4.md"

doc/appendix-release-notes.sgml

@@ -32,6 +32,14 @@
     <xref linkend="upgrading-from-repmgr-3">.
   </para>
 
+  <note>
+    <para>
+      To standardise terminology, from this release <literal>primary</literal> is used to
+      denote the read/write node in a streaming replication cluster. <literal>master</literal>
+      is still accepted as an alias for &repmgr; commands
+      (e.g. <link linkend="repmgr-primary-register"><command>repmgr master register</command></link>).
+    </para>
+  </note>
   <sect2>
     <title>New command line options</title>
     <para>

doc/changes-in-repmgr4.md

@@ -1,106 +1,7 @@
+Changes in repmgr 4
+===================
 
-Standardisation on `primary`
+This document has been integrated into the main repmgr documentation
-----------------------------
+and is now located here:
 
-To standardise terminology, `primary` is used to denote the read/write
+    https://repmgr.org/docs/release-4.0.html
-node in a streaming replication cluster. `master` is still accepted
-as a synonym (e.g. `repmgr master register`).
-
-
-New command line options
-------------------------
-
-- `--dry-run`: repmgr will attempt to perform the action as far as possible
-   without making any changes to the database
-
-- `--upstream-node-id`: use to specify the upstream node the standby will
-  connect later stream from, when cloning a standby. This replaces the configuration
-  file parameter `upstream_node`, as the upstream node is set when the standby
-  is initially cloned, but can change over the lifetime of an installation (due
-  to failovers, switchovers etc.) so it's pointless/confusing keeping the original
-  value around in the config file.
-
-Changed command line options
-----------------------------
-
-### repmgr
-
-- `--replication-user` has been deprecated; it has been replaced by the
-  configuration file option `replication_user`.  The value (which defaults
-  to the user in the `conninfo` string) will be stored in the repmgr metadata
-  for use by  standby clone/follow..
-
-- `--recovery-min-apply-delay` is now a configuration file parameter
-  `recovery_min_apply_delay, to ensure the setting does not get lost when
-  a standby follows a new upstream.
-
-### repmgrd
-
-- `--monitoring-history` is deprecated and has been replaced by the
-  configuration file option `monitoring_history`. This enables the
-  setting to be changed without having to modify system service files.
-
-Changes to repmgr commands
---------------------------
-
-
-### `repmgr cluster show`
-
-This now displays the role of each node (e.g. `primary`, `standby`)
-and its status in separate columns.
-
-The `--csv` option now emits a third column indicating the recovery
-status of the node.
-
-
-Configuration file changes
---------------------------
-
-### Required settings
-
-The following 4 parameters are mandatory in `repmgr.conf`:
-
-- `node_id`
-- `node_name`
-- `conninfo`
-- `data_directory`
-
-
-### Renamed settings
-
-Some settings have been renamed for clarity and consistency:
-
-- `node`: now `node_id`
-- `name`: now `node_name`
-- `master_reponse_timeout`: now `async_query_timeout` to better indicate its
-   purpose
-
-- The following configuration file parameters have been renamed for consistency
-  with other parameters (and conform to the pattern used by PostgreSQL itself,
-  which uses the prefix `log_` for logging parameters):
-  - `loglevel` has been renamed to `log_level`
-  - `logfile` has been renamed to `log_file`
-  - `logfacility` has been renamed to `log_facility`
-
-### Removed settings
-
-- `cluster`: has been removed
-- `upstream_node`: see note about `--upstream-node-id` above.
-- `retry_promote_interval_secs`: this is now redundant due to changes in the
-   failover/promotion mechanism; the new equivalent is `primary_notification_timeout`
-
-
-### Logging changes
-
-- default value for `log_level` is `INFO` rather than `NOTICE`.
-- new parameter `log_status_interval`, which causes `repmgrd` to emit a status log
-  line at the specified interval
-
-
-repmgrd
--------
-
-The `repmgr` shared library has been renamed from `repmgr_funcs` to `repmgr`,
-meaning `shared_preload_libraries` needs to be updated to the new name:
-
-    shared_preload_libraries = 'repmgr'

doc/upgrading-repmgr.sgml

@@ -23,6 +23,11 @@
   file used by <application>repmgrd</application>; check the release notes for details.
  </para>
 
+ <para>
+   Please check the <link linkend="appendix-release-notes">release notes</link> for every
+   release as they may contain upgrade instructions particular to individual versions.
+ </para>
+
  <sect1 id="upgrading-from-repmgr-3" xreflabel="Upgrading from repmgr 3.x">
   <indexterm>
    <primary>upgrading</primary>