Heat Recovery check on

[Fred Buhl <buhl@xxxxxxxxxxxxx>]

I've checked in a new module HeatRecovery.f90.
Other modules that have changed are:

SimAirServingZones
MixedAir
Humidifiers
SetPointManager
Zoneequipmentmanager

And: Energy+.idd

New inputs are:

TermRhOAHeatRec.idf
TermRhOAHeatRec.rvi

HeatRecovery.f90 contains a model of a flat plate
heat exchanger (from Michael Wetter) with the usual
flow arrangements. The new input illustrates the use of
the heat exchanger to recover heat from the system relief
air. 

Changes I made to SimAirServingZones will cause small changes
to all of the inputs using central air systems.

Fred Buhl