* Make ResultCache max_size configurable
fixes#463
* Add tests and docs.
* fix documentation...
...adapt the source, not the auto-generated man pages themselves as
requested in #544.
* fix typo.
Except for tests that include non-unicode characters:
tests/test_po.py
tests/test_strformat.py
tests/test_url.py
tests/checker/test_error.py
tests/checker/test_news.py