Adds hints which finger to use for which key

[HiranChaudhuri]

I really like that the keyboard is displayed on-screen so typists will learn not to look at the keyboard. Even better you indicate which key needs to be pressed.

For the completely innocent user it is not clear though which finger to use. I interpreted the key colors as that information, but looking at my practice I deviate. So I'm not sure if the colors are wrong or just not meant to depict the range of the fingers. Or is it me having learned a wrong style?

For that reason it would be worth indicating which finger to move. This might be done using arrows, as you do already in the statistics.

[tomasz-torcz-airspace-intelligence]

Related: https://github.com/aradzie/keybr.com/issues/90