CVset (which was a silly name) renamed to Namespace
Namespace unification - words, globals and constants are now all fundamentally the same thing.
This is a big change, so might cause problems, although all the tests pass.
A rather epic bug fix, to do with the way that arraylists are both
chunks of raw memory and collections of objects. Reducing the size
of the array left a stale copy of the last object, which would then
get destructed - decrementing its refcount, causing it to be deleted
twice.