docs: miscellaneous updates

HISTORY

@@ -1,6 +1,6 @@
-4.0     2017-10-04
-        Complete rewrite with many changes; see file "doc/upgrading-from-repmgr3.md"
-        for details.
+4.0.0   2017-11-21
+        Complete rewrite with many changes; for details see the repmgr 4.0.0 release
+        notes at: https://repmgr.org/docs/4.0/release-4.0.html
 
 3.3.2   2017-06-01
         Add support for PostgreSQL 10 (Ian)

doc/quickstart.sgml

@@ -5,12 +5,17 @@
   This section gives a quick introduction to &repmgr;, including setting up a
   sample &repmgr; installation and a basic replication cluster.
  </para>
-
  <para>
-  These instructions are not suitable for a production install, as they may not
-  take into account security considerations, proper system administration
-  procedures etc..
+  These instructions for demonstration purposes and are not suitable for a production
+  install, as issues such as account security considerations, and system administration
+  best practices are omitted.
  </para>
+ <note>
+   <simpara>
+     To upgrade an existing &repmgr; 3.x installation, see section
+     <xref linkend="upgrading-from-repmgr-3">.
+   </simpara>
+ </note>
 
  <sect1 id="quickstart-prerequisites">
    <title>Prerequisites for setting up a basic replication cluster with &repmgr;</title>

doc/upgrading-repmgr.sgml

@@ -179,9 +179,10 @@
       changed.
     </para>
     <para>
-      Please note that the parameter <varname>data_directory</varname> <emphasis>must</emphasis>
-      be provided; if not already present, the conversion script will add an empty
-      placeholder parameter.
+      Please note that the the conversion script will add an empty
+      placeholder parameter for <varname>data_directory</varname>, which
+      is a required parameter in repmgr4 and which <emphasis>must</emphasis>
+      be provided.
     </para>
    </sect3>
   </sect2>