issue 2240 when no addon are installed hint the location of sources in the admin panel

mod/admin.php

@@ -1441,6 +1441,8 @@ function admin_page_plugins(&$a){
 		'$baseurl' => $a->get_baseurl(true),
 		'$function' => 'plugins',
 		'$plugins' => $plugins,
+		'$pcount' => count($plugins), 
+		'$noplugshint' => sprintf( t('There are currently no plugins available on your node. You can find the official plugin repository at %1$s and might find other interesting plugins in the open plugin registry at %2$s'), 'https://github.com/friendica/friendica-addons', 'http://addons.friendi.ca'),
 		'$form_security_token' => get_form_security_token("admin_themes"),
 	));
 }

view/templates/admin_plugins.tpl

@@ -2,6 +2,11 @@
 <div id='adminpage'>
 	<h1>{{$title}} - {{$page}}</h1>
 		<a class="btn" href="{{$baseurl}}/admin/{{$function}}?a=r&amp;t={{$form_security_token}}">{{$reload}}</a>
+		{{if $pcount eq 0}}
+		    <div class="XXX">
+		    {{$noplugshint}}
+		    </div>
+		{{else}}
 		<ul id='pluginslist'>
 		{{foreach $plugins as $p}}
 			<li class='plugin {{$p.1}}'>
@@ -13,4 +18,5 @@
 			</li>
 		{{/foreach}}
 		</ul>
+		{{/if}}
 </div>