Added Link to compose plugin install guide

overrides/main.html

@@ -1,6 +1,6 @@
 {% extends "base.html" %}
 
 {% block announce %}
-  <center><h4>Alle Befehle sind gemäß der Syntax des Docker Compose Plugins beschrieben.<br>
+  <center><h4>Alle Befehle sind gemäß der Syntax des <a href="https://docs.docker.com/compose/install/linux/">Docker Compose Plugins</a> beschrieben.<br>
-    All commands are written according to the Docker Compose Plugin syntax.</h4></center>
+    All commands are written according to the <a href="https://docs.docker.com/compose/install/linux/">Docker Compose Plugin</a> syntax.</h4></center>
 {% endblock %}