Main entry point for CLI

[viesti]

tools.cli has support for dividing cli argument processing to subcommands via in-order Processing for Subcommands. Using this we could have a main entry point for pack.alpha, that could have common options and could provice help for all commands it supports via shared -h option.

[SevereOverfl0w]

I've been waiting for a good reason to break the api. Being alpha helps make it okay. I was thinking I would go for juxt.pack as the main.

I hadn't given much thought to whether -h should be before or after the sub-command, same for the other common flags.