From e71a4dcf5538a1417330eb8ebc5136907ab7a860 Mon Sep 17 00:00:00 2001
From: Jerry Wu <wzhongyuan@gmail.com>
Date: Fri, 25 Aug 2017 08:25:40 +0800
Subject: [PATCH] Serialization - version control & python API (#1491)

* add version control

* version support

* add python api

* add version control proto

* add unit test

* change function name

* rename function api

* per comments

* refinement to make hierachy more cleaner

* backward compatibility