Welcome mechanism to login users (hhucn/adhocracy.hhu_theme#169)
"welcome" feature: Add password setting dialog (hhucn/adhocracy.hhu_theme#169)
Enable welcome in hhu config
Nicer default if welcome auth fails
Better error message if password is too short
Send passwort change request in background
Default enable_welcome to off
Merge branch 'develop' into welcome

Conflicts:
	buildouts/hhu.cfg
	src/adhocracy/static/stylesheets/screen/content.css
pep8 beautification
Bump migration version number
Merge pull request #282 from phihag/welcome

Improve initial experience for invited users