Redo README, add RAM requirements - elastic#13

Toby McLaughlin · Toby McLaughlin · commit 219d9d9e7e81 · 2017-10-12T14:48:26.000+11:00
diff --git a/README.md b/README.md
@@ -1,9 +1,24 @@
 # stack-docker
-Meta-project for the Elastic Docker images.
+This example Docker Compose configuration demonstrates many components of the
+Elastic Stack, all running on a single machine under Docker.
 
-## Quick Demo
+## Prerequisites
+- Docker and Compose. Windows and Mac users get Compose installed automatically
+with Docker. Linux users can:
+```
+pip install docker-compose
+```
+
+- At least 4GiB of RAM for the containers. Windows and Mac users _must_
+configure their Docker virtual machine to have more than the default 2 GiB of
+RAM:
+
+![Docker VM memory settings](screenshots/docker-vm-memory-settings.png)
+
+## Starting the stack
 Try `docker-compose up` to create a demonstration Elastic stack with
-Elasticsearch, Kibana, Logstash, Auditbeat, Metricbeat, Filebeat, Packetbeat, and Heartbeat.
+Elasticsearch, Kibana, Logstash, Auditbeat, Metricbeat, Filebeat, Packetbeat,
+and Heartbeat.
 
 Point a browser at `http://localhost:5601` to see the results.
 
