add utf-8 headers
refactor settings

move frigg specific variables to settings.frigg
Update flake8 config
Add environment specific requirements files
Add clean command to Makefile
Change settings import to use django.conf.settings
Set correct django version
Change to local imports in settings.__init__
Change requirements file in tox
Use make to copy local settings in tox

It avoids overwriting a custom local.py
Merge branch 'master' of github.com:frigg/frigg into clean

Conflicts:
	frigg/settings/base.py
	requirements.txt
Add /usr/bin/make to tox whitelist
Remove requirements.txt
Merge branch 'master' of github.com:frigg/frigg into clean

Conflicts:
	frigg/builds/admin.py
Merge pull request #59 from frigg/clean

Clean