Motivations:
- consistency - we generally use expanded names, and this also
matches Qt API which uses Database instead of Db
- avoids unpredictable capitalization throughout API (mix of "Db"
and "DB")
Now all classes and members are either exposed to bindings or marked
as "not available in Python bindings" in the docs.
Drop test thresholds to 0. Now it should be much easier to determine
what missing members have been added which are causing test
failures.