Use distribute on Travis CI

Travis has an old version of setuptools so we explicitly need to tell
bootstrap.py to use distribute.
Use plone.recipe.codeanalysis

Integrate plone.recipe.codeanalysis in the buildout and correct the trivials
errors.
Upgrade the version of plone.recipe.codanalysis to 1.0b5 to get the fixes and activate options needed
Remove bin/flake8 command since bin/code-analysis is calling it
garden