Create upgrade notes

doc/manual/installation/upgrading.xml

@@ -0,0 +1,21 @@
+<chapter xmlns="http://docbook.org/ns/docbook"
+      xmlns:xlink="http://www.w3.org/1999/xlink"
+      xmlns:xi="http://www.w3.org/2001/XInclude"
+      version="5.0"
+      xml:id="ch-upgrading-nix">
+
+  <title>Upgrading Nix</title>
+
+  <para>
+    Multi-user Nix users on macOS can upgrade Nix by running
+    <command>sudo -i sh -c 'nix-channel --update &amp;&amp; nix-env
+    -iA nixpkgs.nix'; sudo launchctl stop org.nixos.nix-daemon; sudo
+    launchctl start org.nixos.nix-daemon</command>.
+  </para>
+
+  <para>
+    Single-user installations of Nix should run <command>nix-channel
+    --update; nix-env -iA nixpkgs.nix</command>.
+  </para>
+
+</chapter>

doc/manual/manual.xml

@@ -32,6 +32,7 @@
 
   <xi:include href="introduction/introduction.xml" />
   <xi:include href="installation/installation.xml" />
+  <xi:include href="installation/upgrading.xml" />
   <xi:include href="packages/package-management.xml" />
   <xi:include href="expressions/writing-nix-expressions.xml" />
   <xi:include href="advanced-topics/advanced-topics.xml" />

doc/manual/release-notes/rl-2.1.xml

@@ -74,13 +74,6 @@ new features:</para>
 
 </itemizedlist>
 
-<para>
-  Multi-user Nix users on macOS can upgrade Nix by running
-  <command>sudo -i sh -c 'nix-channel --update &amp;&amp; nix-env -iA
-  nixpkgs.nix'; sudo launchctl stop org.nixos.nix-daemon; sudo
-  launchctl start org.nixos.nix-daemon</command>.
-</para>
-
 <para>This release has contributions from
 
 Adrien Devresse,