ochre

Copperbox revision 2721.

New project - ochre.

This is a reworking of orchsyn with a simpler expression type - as Csound supports if-then-else I think I can avoid lambdas in the expression language, this makes Ochre quite a bit simpler than Orchsyn.

I've implemented the same expression language optimizations as Orchsyn, which means I'm up to converting the expression language into Csound, the big step...