Improve documantion of many plugins

Specifically the configuration examples are now indented properly.

plugins/syncthing/strelaysrv_

@@ -1,34 +1,52 @@
 #!/bin/sh
 : <<=cut
 =head1 NAME
+
 strelaysrv_ - Plugin to monitor Syncthing relay server
 
 =head1 DESCRIPTION
+
 This plugin gathers metrics from a Syncthing relay server.
 
 This plugin requires the jq utility : https://stedolan.github.io/jq/
 This plugin requires the curl utility : https://curl.haxx.se/
 
-Available plugins :
-strelaysrv_goroutine #
-strelaysrv_num       #
-strelaysrv_proxied   #
-strelaysrv_transfer  #
-strelaysrv_uptime    #
+Available wildcard plugin features:
+
+=over 4
+
+=item strelaysrv_goroutine
+
+=item strelaysrv_num
+
+=item strelaysrv_proxied
+
+=item strelaysrv_transfer
+
+=item strelaysrv_uptime
+
+=back
+
 
 =head1 CONFIGURATION
-To make the plugin connect to the Syncthing relay server one has to use this type of
-configuration
-[strelaysrv_*]
 
-env.syncthing_relaysrv_host 127.0.0.1
-env.syncthing_relaysrv_port 22070
+To make the plugin connect to the Syncthing relay server one has to use this type of
+configuration:
+
+ [strelaysrv_*]
+ env.syncthing_relaysrv_host 127.0.0.1
+ env.syncthing_relaysrv_port 22070
 
 =head1 AUTHOR
+
 Pierre-Alain TORET <pierre-alain.toret@protonmail.com>
 
 =head1 LICENSE
+
 MIT
+
+SPDX-License-Identifier: MIT
+
 =cut
 
 syncthing_relaysrv_host=${syncthing_relaysrv_host:-}