man pages for detailed documentation

[UmanShahzad]

There's actually so many features in the CLI so far for different commands that it's not reasonable to lay everything out in the README or in the inlined -h/--help output.

We should create man pages for individual commands which go into full details of what's possible and which can be accessible in these two ways:

$ man 1 ipinfo-<subcommand>
$ ipinfo <subcommand> --help

This is similar to what git does, e.g.:

$ man 1 git-init
$ git init --help

Need to also figure out how this works in a PowerShell (windows) environment.

[UmanShahzad]

Tagging this as something we can do for v2.