group orders: display deposit, tolerance only if necessary

[mjavurek]

In the current foodsoft version, it is not visible for ordergroups during ordering, if articles contain a deposit and ordergroups may think the article is more expensive. Tolerances are currently shown for all articles, even for articles without tolerance, which makes the view unnecessarily complex. This PR resolves both issues:

Tolerances and deposit are not shown if there is none of them:

An additional column is displayed for the deposit if there is at least one article in the order with deposit. This is important for the ordergroups so that they know that the price shown includes a deposit.

If there is at least one article with tolerance (unit quantity > 1), additional columns appear with tolerance information only at corresponding articles.

[mjavurek]

Todos:

• add .contains_deposit in language files

[mjavurek]

Actually, the markup is also calculated for the deposit included in the gross price:

((price + deposit) * (1+tax)) * markup

At least there should be an option to exclude the deposit from the markup, like FoodsoftConfig[:deposit_with_markup]:

(price * (1+tax)) * markup + (deposit * (1+tax))