alternate login form (hhucn/adhocracy.hhu_theme#168)

The alternate, Amazon-style login form may offer usability benefits (We'll test whether it really does).
pep8
Simplify registration support email
Merge remote-tracking branch 'liqd/develop' into alternative-login-form

Conflicts:
	buildouts/hhu.cfg
	src/adhocracy/static/stylesheets/screen/content.css
Merge remote branch 'origin/develop' into alternative-login-form

Conflicts:
	src/adhocracy/controllers/user.py
Merge remote branch 'origin/develop' into alternative-login-form

Conflicts:
	buildouts/hhu.cfg
Merge pull request #334 from phihag/alternative-login-form

alternate login form (hhucn/adhocracy.hhu_theme#168)