Add xdg-app info to docs

Add the info command in xdg-app(1), and build the existing
man page for it.

doc/Makefile.am

@@ -25,6 +25,7 @@ man_MANS = \
 	xdg-app-update.1		\
 	xdg-app-uninstall.1		\
 	xdg-app-list.1			\
+	xdg-app-info.1			\
 	xdg-app-make-current.1		\
 	xdg-app-run.1			\
 	xdg-app-override.1		\

doc/xdg-app-info.xml

@@ -2,7 +2,7 @@
 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
     "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
 
-<refentry id="xdg-app-list">
+<refentry id="xdg-app-info">
 
     <refentryinfo>
         <title>xdg-app info</title>

doc/xdg-app.xml

@@ -134,6 +134,13 @@
                     List installed applications and/or runtimes.
                 </para></listitem>
             </varlistentry>
+            <varlistentry>
+                <term><citerefentry><refentrytitle>xdg-app-info</refentrytitle><manvolnum>1</manvolnum></citerefentry></term>
+
+                <listitem><para>
+                    Show information for an installed application or runtime.
+                </para></listitem>
+            </varlistentry>
         </variablelist>