Add prices to reservation templates

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Wehn using the template for reservations either the mail or PDF template there is no way to include the price of the reservation at the moment.
The price of a reserveration should be automatically included based on existing price classes.
The following new variables must be available in a reservation template:

• sumApartmentment -> total price of all apartments for all selected reservations
• sumMisc -> total price of all miscellaneous prices of the selected reservations
• totalPrice -> total price of all room and miscellaneous prices of the selected reservations
• apartmentPositions -> an array of all room prices (including totalPrice for the current room), this replaces the old reservations array which holds the same inforation but not the price inforamtion
• miscPositions -> an array of all miscellenous prices