Cleanup and bbb removal

Reduced dependencies and declared them explicit.
Do not directly depend on ``Products.CMFPlone`` any more.
Pep8fied et al.
ATCT is now an extra require.
Skip Zope2 old style interfaces.
Stop Plone 3 support in 1.1 series (remove bbb+patches).
Get rid of old outdated interface fallbacks.
I guess that both id -> iid are due to not trying to shadow built-in [id](https://docs.python.org/2/library/functions.html#id)?