Augmentation dots of multi-voice notes not aligned independently

When I first worked on the layout stuff, this was not possible - there was just one global position for dots across the chord. Werner changed the dot implementation later and I think it's possible now to do this. I'll look into it.

This does open a bit of a can of worms. We actually rely on the fact that dots are all aligned by default in certain combinations of overlapping chords where this ends up being the correct behavior - or at least, one of two behaviors sanctioned by Gould (eg, the both-parts-dotted example she gives later on that same page, and also on the next page, when in "cramped conditions"). Changing the dot positioning algorithm to allow different voices to have different dot positions would also allow us to use the other sanctioned approach in those situations. But more importantly, either way, it means having to partially re-implement those other cases so "fixing" this case doesn't break the others. In other words, even to keep the same behavior for the other cases, we'd have to do extra work.

Bottom line, this would be a higher-risk change than I might have hoped. Deferring for now as I expect this to be a very uncommon case, and at least the defaults are predictable and manual override is easy. And the way these particular manual overrides are stored, they should continue to be safe even if the defaults change.