Transition to pyflakes 0.6.1

That was less painful than I thought it would be.
Add error numbers to pyflakes messages
Fixes #58
Fixes #66

flake8 will defer to local configurations first but then will check global
per-user configuration
Bump to pep8 1.4.2 to remove some hacks

I'm so glad this came out.
Fix tests
Further simplification thanks to pep8