doc: update documentation and sample env file

env.example

@@ -1,11 +1,35 @@
-CONFIG=~/tmp-cfg
+# Directory where all configuration will be stored.
+CONFIG=~/.jitsi-meet-cfg
+
+# System time zone.
 TZ=Europe/Amsterdam
+
+# Internal XMPP domain. You generally don't need to change this.
 XMPP_DOMAIN=meet.jitsi
+
+# Internal XMPP domain for authenticated services. You generally don't need to
+# change this.
 XMPP_AUTH_DOMAIN=auth.meet.jitsi
+
+# XMPP BOSH URL base. You generally don't need to change this.
 XMPP_BOSH_URL_BASE=http://xmpp.meet.jitsi:5280
+
+# XMPP component password for Jitsi Videobridge.
 JVB_COMPONENT_SECRET=s3cr3t
+
+# STUN servers used to discover the server's public IP.
 JVB_STUN_SERVERS=stun.l.google.com:19302,stun1.l.google.com:19302,stun2.l.google.com:19302
+
+# XMPP component password for Jicofo.
 JICOFO_COMPONENT_SECRET=s3cr37
+
+# XMPP user for Jicofo client connections. You generally don't need to change
+# this. NOTE: this option doesn't currently work due to a bug.
 JICOFO_AUTH_USER=focus
+
+# XMPP password for Jicofo client connections.
 JICOFO_AUTH_PASSWORD=passw0rd
 
+# IP addrss of the Docker host. See the "Running on a LAN environment" section
+# in the README.
+#DOCKER_HOST_ADDRESS=192.168.1.1