Switched setup.py to setuptools.
Skipped inclusion of scripts (pip will take care of that).
Changed setup.py to use find_packages.
Refs #21628 -- removed one usage of the imp module in the tests. It is deprecated in Python 3.4
Fixed Oracle query failures caused by lookup refactor

Refs #21821.
Fixed #21825 -- gis compiler uses self instead of qn for as_sql()
Merge pull request #2116 from apollo13/setuptools

 Switched setup.py to setuptools.
Fixed #18907 -- Correct docs regard population of model backrefs.

Thanks simonpercivall for the report and Aymeric for the patch.
Implement swappable model support for migrations
Fixed #21783: Use defaults for adding NOT NULL on sqlite
Fix unicode default input on py3
Fixed #21323 -- Improved readability of serialized Operation.
Merge pull request #1681 from loic/migrations.format

Fixed #21323 -- Improved readability of serialized Operation.
Fixed #21783: (again) Found second source of bug, also squashed it.
Fixed #21786: Bad behaviour when mixins + abstract bases for migrations
Fixed #21664: Multi-table inheritance was duplicating _ptr fields
Fixed #21638: Validators are now comparable, stops infinite user mig'ns
Remove unicode prefix that snuck in
Remove other unicode literal
Moved the loader tags registration with the other builtins.