Add i18n catalog to checkout view.
Add translations for VendorReport.

Conflicts:
	kirppu/app/static/js/checkout/itemreporttable.coffee
	kirppu/app/static/js/checkout/itemreporttable.js
	kirppu/app/static/js/checkout/vendorreport.coffee
	kirppu/app/static/js/checkout/vendorreport.js