Music XML Input - AaronDavidNewman/Smoosic GitHub Wiki

Implemented music XML input - for the features we support. Smoosic can read in all the xml scores in https://opensheetmusicdisplay.github.io/ and display something close to what the DOM tells us to. Output for xml is underway.

Also added basic score landmarks (title, composer) to the DOM. I still need to figure out a better way to represent general, non-musical text in the SMO model.