functional-tester: plog for milli-second timestamp

Standard log package by default only prints out the second-scale
so the 3rd party log feeder mixes the order of the events, which makes
the debugging hard. This replaces it with capnslog and make them consistent
with all other etcd log formats.

tools/functional-tester/etcd-agent/main.go

@@ -16,11 +16,14 @@ package main
 
 import (
 	"flag"
-	"log"
 	"os"
 	"path/filepath"
+
+	"github.com/coreos/etcd/Godeps/_workspace/src/github.com/coreos/pkg/capnslog"
 )
 
+var plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "etcd-agent")
+
 func main() {
 	etcdPath := flag.String("etcd-path", filepath.Join(os.Getenv("GOPATH"), "bin/etcd"), "the path to etcd binary")
 	etcdLogPath := flag.String("etcd-log-path", "etcd.log", "the path to etcd log")
@@ -29,7 +32,7 @@ func main() {
 
 	a, err := newAgent(*etcdPath, *etcdLogPath)
 	if err != nil {
-		log.Fatal(err)
+		plog.Fatal(err)
 	}
 	a.serveRPC(*port)