Data Calc with dates displays too many operations

Problem/Motivation

Currently, the code for the data_calc action disables only the * and / operation when provided with a date parameter for input1, but the comments seem to point to the fact that the min and max operations should be disabled as well.

Proposed resolution

Either disable the min and max operations or add logic to the action to correctly handle the min and max operations for dates.

My preference would be to add the logic, as there are valid use cases where one would want to compare two dates. We have resorted to writing our own action for those use cases, but having that functionality in rules_core would be even better.