pythonPackages: updates for many packages

* deform -> 2.0a2
* peppercorn -> 0.5
* pyramid -> 1.5.2
* pyramid_tm -> 0.10
* zope_deprecation -> 4.1.2
* venusian -> 1.0
* flake8 -> 2.3.0
* mccabe -> 0.3
* pg8000 -> 1.10.1
* turses -> 0.2.23
* urwid -> 1.3.0
* waitress -> 0.8.9
* translationstring -> 1.3