Upgraded ElasticSearch and Kibana to 6.1.1

Requires a reset + reindex of everything (well, that's the easiest way to
get things indexed properly again), which will loose us the Cloud stats.
Before doing this, export those to MongDB and upgrade the statscollector
to the version that I'll be committing soon.

docker/docker-compose.yml

@@ -25,7 +25,7 @@ services:
       - "127.0.0.1:5672:5672"
 
   elastic:
-    image:                   armadillica/elasticsearch:latest
+    image:                   armadillica/elasticsearch:6.1.1
     container_name:          elastic
     restart:                 always
     volumes:
@@ -45,7 +45,7 @@ services:
       - elastic
 
   kibana:
-    image:                   armadillica/kibana:latest
+    image:                   armadillica/kibana:6.1.1
     container_name:          kibana
     restart:                 always
     environment: