vendor: Add missing package dependencies

Gopkg.toml

@@ -28,3 +28,8 @@
 [[constraint]]
   name = "github.com/hashicorp/yamux"
   revision = "f5742cb6"
+
+[prune]
+  non-go = true
+  go-tests = true
+  unused-packages = true

proxy.go

@@ -183,7 +183,7 @@ func printAgentLogs(sock string) error {
 }
 
 func setupNotifier() chan os.Signal {
-	sigCh := make(chan os.Signal)
+	sigCh := make(chan os.Signal, 8)
 	signal.Notify(sigCh, termSignal)
 
 	return sigCh

proxy_test.go

@@ -49,7 +49,7 @@ func client(proxyAddr, file string) error {
 		}
 		sum1 = fmt.Sprintf("%x", h.Sum(nil))
 
-		_, err = f.Seek(0, os.SEEK_SET)
+		_, err = f.Seek(0, io.SeekStart)
 		if err != nil {
 			return err
 		}