feat(scripts/test-cluster): create three proxy nodes

This uses some sleep hackery to make sure that window 1 has followers
and window 2 has proxy machines. Seems to work!

scripts/test-cluster

@@ -1,10 +1,11 @@
-#!/bin/bash
+#!/bin/bash -x
 SESSION=etcd-cluster
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
 ulimit -n unlimited
 
 tmux new-session -d -s $SESSION
+mkdir test-cluster
 
 peer_args=
 if [ -n "${DISCOVERY_URL}" ]; then
@@ -15,7 +16,7 @@ fi
 tmux new-window -t $SESSION:1 -n 'peers'
 tmux split-window -h
 tmux select-pane -t 0
-tmux send-keys "${DIR}/../bin/etcd -peer-addr 127.0.0.1:7001 -addr 127.0.0.1:4001 -data-dir peer1 -name peer1 ${peer_args}" C-m
+tmux send-keys "${DIR}/../bin/etcd -peer-addr 127.0.0.1:7001 -addr 127.0.0.1:4001 -data-dir test-cluster/peer1 -name peer1 ${peer_args}" C-m
 
 if [ -z "${peer_args}" ]; then
 	peer_args="-peers 127.0.0.1:7001"
@@ -24,7 +25,18 @@ fi
 for i in 2 3; do
 	tmux select-pane -t 0
 	tmux split-window -v
-	tmux send-keys "${DIR}/../bin/etcd -cors='*' -peer-addr 127.0.0.1:700${i} -addr 127.0.0.1:400${i} -data-dir peer${i} -name peer${i} ${peer_args}" C-m
+	tmux send-keys "sleep 2; ${DIR}/../bin/etcd -cors='*' -peer-addr 127.0.0.1:700${i} -addr 127.0.0.1:400${i} -data-dir test-cluster/peer${i} -name peer${i} ${peer_args}" C-m
+done
+
+tmux new-window -t $SESSION:2 -n 'proxy'
+tmux split-window -h
+tmux select-pane -t 0
+tmux send-keys "curl -XPUT -H \"Content-Type: application/json\" -d '{\"activeSize\":3, \"promoteDelay\":30}' http://127.0.0.1:7001/config" C-m
+
+for i in 4 5 6; do
+	tmux select-pane -t 0
+	tmux split-window -v
+	tmux send-keys "sleep 5; ${DIR}/../bin/etcd -cors='*' -peer-addr 127.0.0.1:700${i} -addr 127.0.0.1:400${i} -data-dir test-cluster/peer${i} -name peer${i} ${peer_args}" C-m
 done
 
 # Attach to session