- make the purpose more explicit, and reduces some work for the
  compiler as well.

At the specie level:
    hs = sensible enthalpy
    ha = absolute (what was total) enthalpy
    es = sensibly internal energy
    ea = absolute (what was total) internal energy

At top-level
    Rename total enthalpy h -> ha
    Rename sensible enthalpy hs -> h

Combined h, hs, e and es thermo packages into a single structure.

Thermo packages now provide "he" function which may return either enthalpy or
internal energy, sensible or absolute according to the run-time selected form

alphaEff now returns the effective diffusivity for the particular energy which
the thermodynamics package is selected to solve for.

At the specie level:
    hs = sensible enthalpy
    ha = absolute (what was total) enthalpy
    es = sensibly internal energy
    ea = absolute (what was total) internal energy

At top-level
    Rename total enthalpy h -> ha
    Rename sensible enthalpy hs -> h

Combined h, hs, e and es thermo packages into a single structure.

Thermo packages now provide "he" function which may return either enthalpy or
internal energy, sensible or absolute according to the run-time selected form

alphaEff now returns the effective diffusivity for the particular energy which
the thermodynamics package is selected to solve for.

This reverts commit c5bea524.

This reverts commit b18f6cc1.

Exception: applyWallFunctionBoundaryConditions.C cannot split #include
directives.