Abstract sketch toggling behavior into a sound decorator

[lazarcl]

Currently, sketch switching is tightly coupled with the midi at MasterController.controllerChange(). To reduce this, we should create a new InputDecorator object that can handle this behavior.

There is a reason it was implemented this way. As is, if we used the param array to decide whether we should switch a sketch, we would have no way of knowing if the sketch has already been switched this button press. This is because while the button is held down, the program would think that we would like to switch the sketch.

The decorator object would only allow the param array to place the "change sketch" value for one cycle. It then does not allow the 'change sketch' value to be displayed again until the button is released and pressed again.