Bash script for converting sheet music into 3D printer G-code

In my last post, I posted G-code for the startup and shutdown tunes I play on my Rostock Max v2 3D printer.  Those were proof of concept, manually computed using a spreadsheet.  However, once I started, I saw that it would be easy to write a short script to automate turning sheet music into the required G-code to make the printer play music.  Before I explain how it's all done, here's a little of the Tetris Theme to whet your appetite (full explanation and downloads start after the jump):