Show file progress for bootstrap too
Only return one structure from _build_structure
Run unittests from src/
Avoid useless loop in bootstrap (~20x speedup!)
Update bootstrap scores
Fix unittest invocation
Fix headword tests
Prepare 'syntax' along 'structure' and 'roles'

The goal is to replace 'structure' and 'roles' with syntax eventually.
Get back to one factory to avoid FreeBSD kills

(Also, bootstrap is now fast.)