0.4.0 — every name means one thing

No new features. One structural fix, and it breaks an import path.

Changed

• The fold family moved from cjkfold.normalize to cjkfold.folding; the two
  writes moved to cjkfold.rewrite. Nothing about the functions changed —
  from cjkfold import fold, normalize, strip_invisible behaves exactly as it did.

  Why: a function named normalize cannot live in a module named normalize without
  one of the two losing its name, and import a.b as c means c = a.b. So
  import cjkfold.normalize as m handed you the function, and m.fold raised
  AttributeError. Every name now means one thing: cjkfold.normalize is the
  function, cjkfold.folding is the module. (af57ad7)

  What breaks: from cjkfold.normalize import fold — a path nothing ever
  documented, and it now fails with a plain ModuleNotFoundError instead of an
  AttributeError from something that was never a module. Every documented import
  is untouched.

Tests

• scripts/acceptance.py gained import-path checks, including one that the old
  path is gone. (af57ad7)