- in InterfaceCompositionPhaseChangePhaseSystem, the mass transfer
  rates are updated as a side-effect of the massTransfer() method,
  which makes these fields non-const.

- to simplify/unify error handling

STYLE: use NotImplemented instead of longer notImplemented(...)

- pending resolution of cyclic dependencies

Integration of VOF MULES new interfaces. Update of VOF solvers and all instances
of MULES in the code.
Integration of reactingTwoPhaseEuler and reactingMultiphaseEuler solvers and sub-models
Updating reactingEuler tutorials accordingly (most of them tested)

New eRefConst thermo used in tutorials. Some modifications at thermo specie level
affecting mostly eThermo. hThermo mostly unaffected

New chtMultiRegionTwoPhaseEulerFoam solver for quenching and tutorial.

Phases sub-models for reactingTwoPhaseEuler and reactingMultiphaseEuler were moved
to src/phaseSystemModels/reactingEulerFoam in order to be used by BC for
chtMultiRegionTwoPhaseEulerFoam.

Update of interCondensatingEvaporatingFoam solver.