Add missing 'type', 'defaultText' and 'literalExample' in module definitions

- add missing types in module definitions
- add missing 'defaultText' in module definitions
- wrap example with 'literalExample' where necessary in module definitions

nixos/modules/services/monitoring/munin.nix

@@ -122,21 +122,6 @@ in
           HTML output is in <filename>/var/www/munin/</filename>, configure your
           favourite webserver to serve static files.
         '';
-        example = literalExample ''
-          services = {
-             munin-node.enable = true;
-             munin-cron = {
-               enable = true;
-               hosts = '''
-                 [''${config.networking.hostName}]
-                 address localhost
-               ''';
-               extraGlobalConfig = '''
-                 contact.email.command mail -s "Munin notification for ''${var:host}" someone@example.com
-               ''';
-             };
-          };
-        '';
       };
 
       extraGlobalConfig = mkOption {
@@ -147,6 +132,9 @@ in
           Useful to setup notifications, see
           <link xlink:href='http://munin-monitoring.org/wiki/HowToContact' />
         '';
+        example = ''
+          contact.email.command mail -s "Munin notification for ''${var:host}" someone@example.com
+        '';
       };
 
       hosts = mkOption {