Appease the vndr God

Adjust paths that were not canonical.

Add nested vendors that are required.

Now no errors with latest `vndr`.

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

vendor/github.com/godbus/dbus/transport_darwin.go

@@ -0,0 +1,6 @@
+package dbus
+
+func (t *unixTransport) SendNullByte() error {
+	_, err := t.Write([]byte{0})
+	return err
+}