Document nginx vserver setup

deploy/vserver.env.example

@@ -1,14 +1,18 @@
 # SSH host or alias from ~/.ssh/config.
-REMOTE_HOST=myvserver
+# This can also be a literal user@host value, for example root@myvserver.
+REMOTE_HOST=root@myvserver
 
 # Remote filesystem layout.
-REMOTE_APP_DIR=/opt/rolemasterdb
-REMOTE_DATA_DIR=/opt/rolemasterdb/data
+REMOTE_APP_DIR=/root/docker/rolemasterdb
+REMOTE_DATA_DIR=/root/docker/rolemasterdb/data
 
 # Docker names on the remote host.
 IMAGE_NAME=rolemasterdb
 CONTAINER_NAME=rolemasterdb
 
+# Bind the container only on loopback so nginx is the public entrypoint.
+HOST_BIND_ADDRESS=127.0.0.1
+
 # Port mapping: host:container.
 HOST_PORT=8080
 CONTAINER_PORT=8080