thermoSingleLayer → phaseChangeModel Relation

File in src/regionModels/surfaceFilmModels/thermoSingleLayer	Includes file in src/regionModels/surfaceFilmModels/submodels/thermo/phaseChangeModel/phaseChangeModel
thermoSingleLayer.C	phaseChangeModel.H
thermoSingleLayerI.H	phaseChangeModel.H