Add keywise WPM and accuracy data to the results about ttyper

[reaganmcf]

@max-niederman Awesome, let me know when you merge it into master and then I'll rewrite and finish my PR 👍🏻

[reaganmcf]

I would like to work on this 😄

[reaganmcf]

I laid out the rough outline for this solution right now but it's a little hacky in my opinion. Storing the keys as [Fraction; 256] makes it really annoying to get the data, particularly sorting to get the worst keys. I feel like rewriting to use a HashMap<char, Fraction> would be much cleaner and more extendible. @max-niederman What do you think?

// get top 5 worst keys
let mut worst_key_display_str = String::from("Worst Keys:");
let mut key_and_cps_list: Vec<(char, f64)> = Vec::new();
for i in 0..256 {
    let temp = self.cps.per_key[i];
    let ascii_char = i as u8 as char;
    if temp.is_nan() || ascii_char == AsciiChar::BackSpace {
        continue;
    }
    key_and_cps_list.push((ascii_char, temp));
}
key_and_cps_list.sort_by(|a, b| {
    let f1 = a.1;
    let f2 = b.1;
    f1.partial_cmp(&f2).unwrap()
});
for key_and_cps_pair in key_and_cps_list[0..std::cmp::min(key_and_cps_list.len(), 5)].iter()
{
    worst_key_display_str = format!(
        "{}\n- '{}' at {:.2} cps",
        worst_key_display_str, key_and_cps_pair.0, key_and_cps_pair.1
    );
}
info_text.extend(Text::from(worst_key_display_str))

Below is an example of the output. I'm not really feeling this implementation with cps, and I'm going to use accuracy instead.

[max-niederman]

Storing the keys as [Fraction; 256] makes it really annoying to get the data, particularly sorting to get the worst keys. I feel like rewriting to use a HashMap<char, Fraction> would be much cleaner and more extendible.

Yeah, it would probably be a good idea to rewrite the results to use a HashMap<char, T> not only for this feature, but also to better support unicode.

[max-niederman]

Actually, now I think about it, we could just use a HashMap<KeyEvent, T>. @reaganmcf I'm going to work on switching to HashMap for the Results code.

[max-niederman]

@reaganmcf I've merged the changes with master