Add a Touch Typing Tutorial to DrRacket

[OrionRandD]

This is a PR:
I think that part of the solution to overcome the Syntax of any programming language is teaching children, teens, adults and everyone who uses a computer, how to touch type. So that, they can type quickly and get to know their keyboard better and concentrate in the language concepts themselves instead of looking to their keyboard keys to do something useful...
I think that every IDE should have a touch typing tutorial as part of the program...
I use Emacs, and I have a package for training touch typing...

See this article:
https://blog.codinghorror.com/we-are-typists-first-programmers-second/

I also suggested it to the Hedy project:
hedyorg/hedy#3770