for setting up baked lazy loaders would interfere with other
loader strategies that rely on lazy loading as a fallback, e.g.
joined and subquery eager loaders, leading to ``IndexError``
exceptions at mapper configuration time.
fixes #3612

the check added for a polymorphic joinedload from a
poly_subclass->class->poly_baseclass connection would fail for the
scenario of class->poly_subclass->class.
fixes #3611

would not bump a version id counter when in use.  The experience
here is still a little rough as the original version id is required
in the given dictionaries and there's not clean error reporting
on that yet.
fixes #3610

insert-default holding columns not otherwise included in the SET
clause (such as primary key cols) to get rendered into the RETURNING
even though this is an UPDATE.

- Major fixes to the :paramref:`.Mapper.eager_defaults` flag, this
flag would not be honored correctly in the case that multiple
UPDATE statements were to be emitted, either as part of a flush
or a bulk update operation.  Additionally, RETURNING
would be emitted unnecessarily within update statements.

fixes #3609

cause a subsequent call to the :meth:`.Query.with_parent` method to
fail. fixes #3606
- add mark-as-fail test for #3607

to the :class:`.mutable.MutableDict` class.
fixes #3605

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

the :class:`.Select` construct would have its ``._raw_columns``
collection mutated in-place when compiling the :class:`.Insert`
construct, when the target :class:`.Table` has Python-side defaults.
The :class:`.Select` construct would compile standalone with the
erroneous column present subsequent to compilation of the
:class:`.Insert`, and the the :class:`.Insert` statement itself would
fail on a second compile attempt due to duplicate bound parameters.
fixes #3603

- add version switch for backend fsp test

(cherry picked from commit 67b22cee3ab2c17b61100f1ccd69081082c0f074)