Added the ability to find a list of available dish modifiers considering price categories

Starting from V7, it will be possible to find a list of available modifiers considering price categories for dishes with and without modifier schemes. This will allow displaying the composition of modifiers in the menu in establishments that work with price categories and orders for changing the price list, when a particular modifier in the dish composition may be available or unavailable depending on the assigned order or section price category.

The methods listed below now accept IPriceCategory as an argument. The parameter is not mandatory, i.e., you can pass null if it is important to know the availability of modifiers without considering the price category.

Getting modifiers for a dish without a modifier scheme:

• Simple modifiers (IProduct.GetSimpleModifiers or IOperationService.GetSimpleModifiersByProduct)
• Group modifiers (IProduct.GetGroupModifiers or IOperationService.GetGroupModifiersByProduct)

Getting modifiers for a dish with a modifier scheme:

• Common simple modifiers (ICompoundItemTemplate.GetCommonSimpleModifiers or IOperationService.GetCommonSimpleModifiersByCompoundItemTemplate)
• Splittable simple modifiers (ICompoundItemTemplate.GetSplittableSimpleModifiers or IOperationService.GetSplittableSimpleModifiersByCompoundItemTemplate)
• Common group modifiers (ICompoundItemTemplate.GetCommonGroupModifiers or IOperationService.GetCommonGroupModifiersByCompoundItemTemplate)
• Splittable group modifiers (ICompoundItemTemplate.GetSplittableGroupModifiers or IOperationService.GetSplittableGroupModifiersByCompoundItemTemplate)