Feature: only show the keyboard after a mistake (or two)

[Yona-Appletree]

brand new colemak learner here

I find it hard not to look at the keyboard indicator while learning, but I think having it there all the time makes it harder for me to learn.

I'd like it only to appear when I make a mistake or two, so that I can focus on the typing when I'm not making mistakes.

Would go well with #42.