- The ORM and Core tutorials, which have always been in doctest format,

- The ORM and Core tutorials, which have always been in doctest format,
are now exercised within the normal unit test suite in both Python
2 and Python 3.
- remove the old testdocs.py runner and replace with test/base/test_tutorials.py
- use pytest's unicode fixer so that we can test for unicode strings
in both py2k/3k
- use py3k format overall for prints, exceptions
- add other fixers to guarantee deterministic results
- add skips and ellipses to outputs that aren't worth matching

(cherry picked from commit d533b8e9223b9c938655e5b666fc928e2d996cd3)