[Review] The first release of Apache DistributedLog

[Sijie Guo]

I drafted a blog post for announcing the first apache release. Here is the
draft. Please help review it :D

https://docs.google.com/document/d/1IXVmP2cHkf4ydeUHUJN9p5ZWTpA1auwBhfqMnYBu4A0/edit

- Sijie