Why have the Arria 10 External Memory Interfaces IP Slew Rate parameters been removed in the Quartus Prime software version 15.1 ?

Description

The Slew Rate parameters in the Board Timing tab have been removed in the Quartus® Prime software version 15.1 as they are not required when the Intersymbol Interference/Crosstalk parameters are determined by the correct simulation flow. This is detailed in the following link : 

Arria_10_EMIF_Simulation_Guidance