switch to go vendoring

vendor/github.com/cevaris/ordered_map/key_pair.go

@@ -0,0 +1,16 @@
+package ordered_map
+
+import "fmt"
+
+type KVPair struct {
+	Key   interface{}
+	Value interface{}
+}
+
+func (k *KVPair) String() string {
+	return fmt.Sprintf("%v:%v", k.Key, k.Value)
+}
+
+func (kv1 *KVPair) Compare(kv2 *KVPair) bool {
+	return kv1.Key == kv2.Key && kv1.Value == kv2.Value
+}