project: use vndr for vendoring

Signed-off-by: Alexander Morozov <lk4d4@docker.com>

vendor/github.com/docker/swarmkit/xnet/xnet_unix.go

@@ -0,0 +1,20 @@
+// +build !windows
+
+package xnet
+
+import (
+	"net"
+	"time"
+)
+
+// ListenLocal opens a local socket for control communication
+func ListenLocal(socket string) (net.Listener, error) {
+	// on unix it's just a unix socket
+	return net.Listen("unix", socket)
+}
+
+// DialTimeoutLocal is a DialTimeout function for local sockets
+func DialTimeoutLocal(socket string, timeout time.Duration) (net.Conn, error) {
+	// on unix, we dial a unix socket
+	return net.DialTimeout("unix", socket, timeout)
+}