removed cmd/ and internal/ - go get -u

[ldemailly]

Comes indirectly from the philosophy on https://github.com/go-standard/project-layout#main

ie if something isn't necessary, don't have it / keep it simple

(I'd also drop go.uber.org/automaxprocs but the reasoning for that is a bit more involved (around cpu limits being bad basically and that auto only knowing about limits))