Allow POST with $apply to invoke an action to an aggregated result

Deferred proposal Add to chapter 3: Service-defined bound actions that take an entity set as their binding parameter MAY be used as the last set transformation within $apply if the type of the binding parameter matches the type of the result set of the preceding transformation. In this case the request MUST be a POST request. Example: Discount all products that meet a filter condition POST Products?$apply=filter(ShelfLife gt duration 'P90D' )/Special.Discount(Percent=15) Note: this example is now possible with  URL Conventions 4.12 Addressing a Subset of a Collection Updated proposal If new use cases arise using other transformations, we may introduce a path segment /$apply(...) that can be followed by the action to call on the aggregated result.