majalan

Copperbox revision 3131.

I've had a major rethink of the Score object. Rather than make it compositional (as per Doc in a pretty print library that supports horizontal and vertical concat), I've made it a finite map of systems. A score is now built by adding (elementary) systems to it - Score is expected to be a singleton within a program.

This greatly simplifies the design of the Score object. It also reduces conceptual overlap between Score and EventList which previously had similar concatenation operations [*]. Now only EventList will have concatenation.

The simplifications to Score should ripple out and lead to simplifications in the rest of the code.

[*] but confusingly different in the details...