Keep an index of compile units in state_t
Keep an index of compile units in state_t

also rename compilation_unit_t -> compile_unit_t.

greig-hamilton/novaprova,greig-hamilton/novaprova,loom-project/novaprova,greig-hamilton/novaprova,novaprova/novaprova,loom-project/novaprova,greig-hamilton/novaprova,novaprova/novaprova,novaprova/novaprova,gnb/novaprova,novaprova/novaprova,novaprova/novaprova,greig-hamilton/novaprova,gnb/novaprova,loom-project/novaprova,loom-project/novaprova,gnb/novaprova,gnb/novaprova,gnb/novaprova