Switch to bjoern WSGI server

(Note that it requires libev development package)
Always show header on dashboard
Merge branch 'master' into bjoern
Merge branch 'master' into bjoern
Merge branch 'master' into bjoern
Changed Python version requirement
This is beta 2 dev version
Extracted new messages
Merge branch 'master' into bjoern
Merge branch 'master' into bjoern

Conflicts:
	librarian/locales/ar/LC_MESSAGES/librarian.po
	librarian/locales/da/LC_MESSAGES/librarian.po
	librarian/locales/de/LC_MESSAGES/librarian.po
	librarian/locales/en/LC_MESSAGES/librarian.po
	librarian/locales/es/LC_MESSAGES/librarian.po
	librarian/locales/fr/LC_MESSAGES/librarian.po
	librarian/locales/hi/LC_MESSAGES/librarian.po
	librarian/locales/it/LC_MESSAGES/librarian.po
	librarian/locales/jp/LC_MESSAGES/librarian.po
	librarian/locales/librarian.pot
	librarian/locales/nb/LC_MESSAGES/librarian.po
	librarian/locales/nl/LC_MESSAGES/librarian.po
	librarian/locales/pt/LC_MESSAGES/librarian.po
	librarian/locales/sr/LC_MESSAGES/librarian.po
	librarian/locales/sv/LC_MESSAGES/librarian.po
	librarian/locales/ta/LC_MESSAGES/librarian.po
	librarian/locales/tr/LC_MESSAGES/librarian.po
	librarian/locales/zh/LC_MESSAGES/librarian.po