- move out "render" types of tests into new test_autogen_render
- clean out test_autogenerate
- start pinning some tests to 0.9, don't need to pin to 0.7 anymore
- Autogenerate for ``op.create_table()`` will not include a
  ``PrimaryKeyConstraint()`` that has no columns.
- don't need a full string test for boolean/check constraint autogen