Function sunrise_shell::subcommands::useradd::main

pub fn main(
    _stdin: IPipeProxy, 
    stdout: IPipeProxy, 
    _stderr: IPipeProxy, 
    args: Vec<String>
) -> Result<(), Error>

Adds a new user to /etc/passwd with the specified username.

The function takes care of prompting for the password in no-echo mode. If an error is returned, then it should be assumed that the user was not added to /etc/passwd.