switch from master branch to tag 3.13.0

[zhangsipeng]

I've used the master branch and encountered some building problems. From other issues I know that I should use a specific tag, so I want to change to 3.13.0. And my question is that if I could change to 3.13.0 without rerunning sync.sh and directly build it since sync costs lots of time.

[vchong]

@zhangsipeng Sorry no. Files (source code) in the master branch and 3.13.0 tag are different and the reason for running sync.sh is to get the proper version of the files for building. There's no other way to change the version without running a sync.