Return 404 for non-existing item.
Update idea config, new versions of django*.
Show error when vendor has no barcodes.
Rename Seller -> Vendor
Rename Cleric -> Clerk
Add some development initial data.
Fix column id.
Rename Registry -> Checkout.
Add event selection to barcode listing.
Add separate errors for inputs of barcode listing.
Add line-ends to terminal url regexps.

- This ensures that parameters are not ignored if they do not match the
  regexp.

Conflicts:
	kirppu/app/urls.py
Implement vendor login.