feat(scripts/test-cluster): add a cluster test command

this uses tmux to setup a test cluster that you can easily kill and
start for debugging.

.gitignore

@@ -2,3 +2,4 @@ src/
 pkg/
 /etcd
 release_version.go
+/machine*

scripts/test-cluster

@@ -0,0 +1,19 @@
+#!/bin/bash
+SESSION=etcd-cluster
+
+tmux new-session -d -s $SESSION
+
+# Setup a window for tailing log files
+tmux new-window -t $SESSION:1 -n 'machines'
+tmux split-window -h
+tmux select-pane -t 0
+tmux send-keys "./etcd -s 127.0.0.1:7001 -c 127.0.0.1:4001 -d machine1 -n machine1" C-m
+
+for i in 2 3; do
+	tmux select-pane -t 0
+	tmux split-window -v
+	tmux send-keys "./etcd -cors='*' -s 127.0.0.1:700${i} -c 127.0.0.1:400${i} -C 127.0.0.1:7001 -d machine${i} -n machine${i}" C-m
+done
+
+# Attach to session
+tmux attach-session -t $SESSION