Simple verse/chorus structure

freezepoint name: V5.1.0 (main)
Changes since last freezepoint (developer/mgr initials and brief description):
Previous significant freezepoint: V5.0.0
DHD20230704: can generate simple house intro/verse/chorus/verse/.../outro, for monthly data.
DHD20230629: initial place-holder chorus generator repeats first data melody bar, w/full tone range.

Initial release

Can generate plain, gentle, house styles.

Some missing and some new functionality compared to V4.x chain.

The house style is now capable of much more structured processing that V4.x.