more friendly errors

Conflicts:
	app/views/layouts/application.html.haml
	public/500.html
	public/503.html
Revert "more friendly errors"

This reverts commit 5570360ddd6cd350e9751050ad1c1356e7fefc2b.
infrastructure for handling errors with exceptions
mailall: hide deleted groups
fix orderdoc when file not found
allow to config margin display on profile
refactor order helpers (see foodcoop-adam#126)
improve receive and distribute (see foodcoop-adam#126)
redesign fax pdf