Use yaml for defining state machines

[rodoufu]

Maybe use gopkg.in/yaml.v2

[igormcoelho]

It's a good idea @rodoufu ... only challenge is to describe transition functions, in a general programming language... if we had some basic language, to operate on machine state data on yaml, and being automatically converted to Java, C++, Go, etc.. this would be nice.

[rodoufu]

I was thinking about using gRPC for that, in the yaml description we say the endpoint, the address and maybe the interface to use.