Smarter Cmdline parsing

[pitermarx]

Currently is very naive

args.Select(a => a.Replace("-", string.Empty).Split("="))
       .ToDictionary(
          pair => pair[0],
          pair => pair.Length > 1 ? pair[1] : "true");

[pitermarx]

Cake.Console has 2 modes

1. RunCakeCli
2. BuildHost

on 1. the parsing is done via spectre console, but on 2. it's still a naive string split