Update vendor dir

vendor/github.com/xenolf/lego/acme/utils.go

@@ -3,16 +3,20 @@ package acme
 import (
 	"fmt"
 	"time"
+
+	"github.com/xenolf/lego/log"
 )
 
 // WaitFor polls the given function 'f', once every 'interval', up to 'timeout'.
 func WaitFor(timeout, interval time.Duration, f func() (bool, error)) error {
+	log.Infof("Wait [timeout: %s, interval: %s]", timeout, interval)
+
 	var lastErr string
-	timeup := time.After(timeout)
+	timeUp := time.After(timeout)
 	for {
 		select {
-		case <-timeup:
-			return fmt.Errorf("Time limit exceeded. Last error: %s", lastErr)
+		case <-timeUp:
+			return fmt.Errorf("time limit exceeded: last error: %s", lastErr)
 		default:
 		}