Add new data center IT equipment model

First draft of source code to add ElectricEquipment:ITE:AirCooled object to model data center IT equipment.
@Myoldmopar Odd.  It ran for me at the time, but I don't recall now if I tested it with a debug or release build.  Will investigate.  Clearly this (and maybe other places) need a trap for this anyway.  And probably some limit checks on the curve evals.