switch to go vendoring

vendor/github.com/stretchr/objx/security.go

@@ -0,0 +1,12 @@
+package objx
+
+import (
+	"crypto/sha1"
+	"encoding/hex"
+)
+
+// HashWithKey hashes the specified string using the security key
+func HashWithKey(data, key string) string {
+	d := sha1.Sum([]byte(data + ":" + key))
+	return hex.EncodeToString(d[:])
+}