Video tutorial bazel

[wonderingabout]

@wodesuck @zxkyjimmy

long time no see :)

so i made this youtube video tutorial to show how to build PhoenixGo on ubuntu 18.04 (still in low quality as i just uploaded it, need to wait a little..)

https://www.youtube.com/watch?v=udXGL1mt92c

i noticed there are small corrections that can be added in the github documentation, so i may submit a PR in the coming days

PhoenixGo's AI style is awesome, would be always happy to see it continue, take care,