Added JSON encoder to disable escaping html symbols

Signed-off-by: Oleh Moskovych <moskovych@gmail.com>

Author: Moskovych

stores/json/store.go

@@ -149,14 +149,24 @@ func (store Store) treeBranchFromJSONDecoder(dec *json.Decoder) (sops.TreeBranch
 	}
 }
 
+// Encoder to disable escaping html symbols
+// See: https://github.com/getsops/sops/issues/881
+func jsonMarshal(v interface{}) ([]byte, error) {
+    buffer := &bytes.Buffer{}
+    encoder := json.NewEncoder(buffer)
+    encoder.SetEscapeHTML(false)
+    err := encoder.Encode(v)
+    return buffer.Bytes(), err
+}
+
 func (store Store) encodeValue(v interface{}) ([]byte, error) {
 	switch v := v.(type) {
 	case sops.TreeBranch:
 		return store.encodeTree(v)
 	case []interface{}:
 		return store.encodeArray(v)
 	default:
-		return json.Marshal(v)
+		return jsonMarshal(v)
 	}
 }