Updated to Version 6

Updated to Graylog to pull Version 6

docker-compose.yml

@@ -52,7 +52,7 @@ services:
     restart: unless-stopped
 
   graylog:
-    image: graylog/graylog:5.1
+    image: graylog/graylog:6.0
     container_name: graylog
     environment:
       # CHANGE ME (must be at least 16 characters)!