adjadext module is missing

[grrrr]

Hey Adam,
the adjadext module is missing in tools/MusicMaker.py, line 5.
If this is an installation requirement setup.py should be fixed.

[adammccartney]

Hi Thomas,

thanks for that, I've added it to the install for the time being, MusicMaker.py is just there for instructional purposes at the moment,
but the rmakers extension is referenced elsewhere (in the _handle_dynamics of RhythmDefinition.py for example). So it makes sense to include it.