- previously introduced `getOrDefault` as a dictionary _get_ method,
  now complete the transition and use it everywhere instead of
  `lookupOrDefault`. This avoids mixed usage of the two methods that
  are identical in behaviour, makes for shorter names, and promotes
  the distinction between "lookup" access (ie, return a token stream,
  locate and return an entry) and "get" access (ie, the above with
  conversion to concrete types such as scalar, label etc).

oversetInterpolationSuppressed dict.

- when constructing dimensioned fields that are to be zero-initialized,
  it is preferrable to use a form such as

      dimensionedScalar(dims, Zero)
      dimensionedVector(dims, Zero)

  rather than

      dimensionedScalar("0", dims, 0)
      dimensionedVector("zero", dims, vector::zero)

  This reduces clutter and also avoids any suggestion that the name of
  the dimensioned quantity has any influence on the field's name.

  An even shorter version is possible. Eg,

      dimensionedScalar(dims)

  but reduces the clarity of meaning.

- NB: UniformDimensionedField is an exception to these style changes
  since it does use the name of the dimensioned type (instead of the
  regIOobject).

Adds overset discretisation to selected physics:
- diffusion : overLaplacianDyMFoam
- incompressible steady : overSimpleFoam
- incompressible transient : overPimpleDyMFoam
- compressible transient: overRhoPimpleDyMFoam
- two-phase VOF: overInterDyMFoam

The overset method chosen is a parallel, fully implicit implementation
whereby the interpolation (from donor to acceptor) is inserted as an
adapted discretisation on the donor cells, such that the resulting matrix
can be solved using the standard linear solvers.

Above solvers come with a set of tutorials, showing how to create and set-up
simple simulations from scratch.

Modification on rhoPimpleFoam pEq's for handling rho thermo and incompressible EoS. Adding rho limiters if p is limited.
This is important when LTS stepping or large Co number is used.

Updating rhoBuoyantPimpleFoam to handle closed domain for rho thermo and incompressible Eos.
Consolidating chtMultiRegionSimpleFoam and chtMultiRegionFoam pEqs to use the same formulation as rhoBuoyantPimpleFoam and
rhoBuoyantSimpleFoam

Henry Weller authored May 17, 2017 and Andrew Heather committed May 17, 2017

79ff91350 - rhoPimpleFoam: Improved support for compressible liquids
(2017-05-17 17:05:43 +0100) <Henry Weller>

Both stardard SIMPLE and the SIMPLEC (using the 'consistent' option in
fvSolution) are now supported for both subsonic and transonic flow of all
fluid types.

rhoPimpleFoam now instantiates the lower-level fluidThermo which instantiates
either a psiThermo or rhoThermo according to the 'type' specification in
thermophysicalProperties, see also commit a1c8cde3

solvers: Moved createRDeltaT.H into createFields.H so that it is available with the -postProcess option

Required to support LTS with the -postProcess option with sub-models dependent on ddt
terms during construction, in particular reactingTwoPhaseEulerFoam.

See also commit cc455173

Now consistent with constructors.

Added calls to setFluxRequired for p, p_rgh etc. in all solvers which
avoids the need to add fluxRequired entries in fvSchemes dictionaries.

so that the effect of the term on the enthalpy equation is optional

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.

Relaxation and solution parameters for the final iteration in PIMPLE loops are
now selected according to the value of the "finalIteration" entry in the
mesh::data dictionary.

rhoPimpleFoam significantly updates and now replaces rhoPisoFoam.

(transient solvers) and corrected paths to the new location of the turbulence models.