pressureInletOutletVelocity/rotatingPressureInletOutletVelocity: Set the normal component of the inlet velocity from the flux rather than the zero-gradient velocity

pressureInletOutletParSlipVelocityFvPatchVectorField: Removed UName option and rationalised operator=

outletPhaseMeanVelocityFvPatchVectorField: New BC for the outlet of a towing-tank to maintain the water level at the same level as the inlet

prghPressure: New pressure BC to allow the specification of a fixed static-pressure distribution in the p_rgh field