error feedback

formatted strings on error feedback

pub enum Feedback{ Info, Warning, Error }

#[test]
fn t001_underline() {
    let s = justify("Hello Goonies!".to_string(), 40, Justify::Center);
    underline_string(s.clone());
    print!("\n");
    let len = s.clone().len();

    assert_eq!(len, 40);
}

#[test]
fn t002_justify() {
    let s = justify("1.5y".to_string(), 7, Justify::Right);
    assert_eq!(s.len(), 7);
}