#1004 Fix memleak in og_cmd_images

image_json object is created to store the json representation of
an image returned by the database. This object is going to be appended
to a json list that will compose the overall root json object.

Use json_array_append_new to let "images" steal the reference of
image_json so when further decref(root) there is no json reference
hanging around.

src/rest.c

@@ -1890,7 +1890,7 @@ static int og_cmd_images(char *buffer_reply)
 			return -1;
 		}
 
-		json_array_append(images, image_json);
+		json_array_append_new(images, image_json);
 	}
 
 	dbi_result_free(result);