Order placement menu: Adapt units/amounts in footer to new unit system

[twothreenine]

This is outdated and confusing:

Suggestion: (omit tolerance for case potatoes, as there's no tolerance input anyway):

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In case of detergent -- old:

Suggestion:

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In case of beer:

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So, my suggestion is:

1. Rename "Filled units" ("Volle Gebinde") to "Order result" ("Bestellergebnis") - it's the amount that will be ordered from the supplier (in supplier order unit) if the minimum order quantity is reached, so it's not only about filling units anymore.
   (this is the most fitting, short label I could think of -- perhaps you know a better one?)
2. Append the supplier order unit to the order result amount
3. Omit "Units: ..." on the left, since it's included in order result
4. Rename "Total units" ("Gesamt-Einheiten") to "Total amount" ("Gesamtmenge"), so that it is consistent with the column titles.
   Omit "Total tolerance" if tolerance input is omitted anyway for the respective article
   Even simpler: Total order: <amount> + <tolerance> <(x) group order unit>
   (mathematically incorrect with the + and x, but shorter and better readable IMO)
   I'd also put Total order above Order result, as it is the more logical way.
5. btw, additionally: Omit missing amount in the table ("0") in case tolerance input is omitted anyway, so that there are less confusing numbers on the screen

[lentschi]

I agree that this is currently a bit confusing and might require a redesign, but I think we could live with the current fields in a first version and move this to the "Post-merge" milestone. (Then we might be able to make such a redesign with more people involved.)