Adding Tutorials to Explain Code

[kinson]

@bvssvni I'm new to Rust and Piston, so I think that the best way for me to contribute while also learning more about both of these things is to create tutorials. That way I can get a better understanding of the codebase by attempting to explain it. I began with a dead-simple, minimal tutorial here . If you could look at the readme and code quickly I would really appreciate any feedback. Feel free to be as pedantic as you want, I'm sure my word choice is sloppy (and technically incorrect) and this process will hopefully refine my knowledge about Rust as well as the Piston framework. Thanks!