map: fix url in iframe

app/views/home/map.html.erb

@@ -2,12 +2,12 @@
 <div style="text-align:center;">
     <h2><%= t('home.mapshots.headline') %></h2>
     <div style="max-width:720;" class="embed-responsive embed-responsive-4by3">
-        <iframe class="embed-responsive-item" src="//illuna-minetest.tk/map" frameborder="0"></iframe>
+        <iframe class="embed-responsive-item" src="map-fullscreen" frameborder="0"></iframe>
     </div>
     <div style="padding-top:10px;"></div>
     <div class="btn-group btn-group-justified" role="group" aria-label="...">
         <div class="btn-group" role="group">
-            <a class="btn btn-primary" href="//illuna-minetest.tk/map-fullscreen" target="_blank">
+            <a class="btn btn-primary" href="map-fullscreen" target="_blank">
                 <i class="glyphicon glyphicon-fullscreen"></i> <%= t('home.mapshots.new_tab') %></a>
         </div>
         <div class="btn-group" role="group">