about to redo the entire project

I just jumped into this without planning, expecting to create something
quick and dirty, but I decided to take my time and redo the entire
project properly.
Redone so far - working on piece movement

I redid almost all of the code I wrote before. I realize that I was
treating the sprites as game objects and using those to do physics. I am
now using 2d vectors to handle the location and movement of the
tetrominos.

Right now, I have to rework how I store the coordinates so when I call
Tetromino::executeMove(), it won't count shapes intersecting with
themselves as a collision.
edited readme