Add new data center IT equipment model

First draft of source code to add ElectricEquipment:ITE:AirCooled object to model data center IT equipment.
@mjwitte In your test file, I am getting a hard crash divide by zero on line 3842 here.  
 - AirMassFlowRate is zero.  
   - The DesignAirVolFlowRate is 10, as I'm guessing it is supposed to be
   - The AirVolFlowFrac variable used above is zero. The arguments to the CurveValue function on line 3827 are:
     - Curve Number = 3
     - CPULoadSchedFrac = 1
     - TAirIn = 2.3

Any thoughts?