Merge branch 'hotfix/2.1.8'
Saferpay payment can't be automatically cancelled

This functionality is only available for Business contracts
or if using the server component (Java or .NET)
Starting 2.1.9 hotfix branch
Show error instead of confirm message if order status notification could not be sent
Speed up variant check
Checkout step "address" could not be completed when a member was logged in (#1271)
Add postAddProductToCollection hook to product collection.
Add postUpdateItemInCollection hook to product collection.
Add postDeleteItemFromCollection hook to product collection.
CS
Order total was not shown in the backend order list (#1282)
Fixed misspelled method name (#1274)
Always load language files in postsale script (#1281)
Correctly format shipping addresses in checkout step (#1278)
Duplicating attribute did not copy the attribute options (#1265)
Rules were not applied to orders (#1290)
The checkout login page is only necessary for member-only checkout
Delete a member's cart when the member is deleted (#1296)
Auto-clean old member carts too
Correctly select "use billing address" when shipping and billing address are the same