repmgr: add "--node-id" option to "cluster cleanup"

Implements GitHub #493.

doc/appendix-release-notes.sgml

@@ -20,6 +20,7 @@
     <para><emphasis>???, 2018</emphasis></para>
     <para>
     </para>
+
     <sect2>
       <title>Configuration file changes</title>
       <para>
@@ -39,6 +40,23 @@
       </para>
 
     </sect2>
+
+    <sect2>
+      <title>repmgr enhancements</title>
+      <para>
+       <itemizedlist>
+
+          <listitem>
+            <para>
+              <command><link linkend="repmgr-cluster-cleanup">repmgr cluster cleanup</link></command>
+              now accepts the <option>--node-id</option> option to delete records for only one
+              node. (GitHub #493).
+            </para>
+          </listitem>
+
+        </itemizedlist>
+      </para>
+    </sect2>
   </sect1>
 
   <sect1 id="release-4.1.1">

doc/repmgr-cluster-cleanup.sgml

@@ -51,6 +51,20 @@
     </para>
   </refsect1>
 
+  <refsect1>
+    <title>Options</title>
+    <variablelist>
+
+      <varlistentry>
+        <term><option>--node-id</option></term>
+        <listitem>
+          <para>
+            Only delete monitoring records for the specified node.
+          </para>
+        </listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
 
   <refsect1>
     <title>See also</title>