Configure sensor models for extensive quantities in steady-state by default

[AntoineGautier]

Using a state to regularize the transition at flow reversal is not needed for variables that are the product of mass flow rate times a measured fluid property. This issue is to set tau = 0 by default for the followings models in IBPSA.Fluid.Sensors.

• EnthalpyFlowRate
• EntropyFlowRate
• LatentEnthalpyFlowRate
• SensibleEnthalpyFlowRate
• VolumeFlowRate

This will also solve a current inconsistency with IBPSA.Fluid.Sensors.UsersGuide that states

Sensors for quantities that are the product of mass flow rate times a measured fluid property: Such quantities include volumentric flow rate or enthalpy flow rate. For these quantities, sensors are by default configured as steady-state sensor.