interFoam family: Added run-time selectable LTS support

LTS is selected by the ddt scheme e.g. in the
tutorials/multiphase/interFoam/ras/DTCHull case:

ddtSchemes
{
    default         localEuler rDeltaT;
}

LTSInterFoam is no longer needed now that interFoam includes LTS
support.

applications/solvers/compressible/rhoCentralFoam/createRDeltaT.H

@@ -1,28 +0,0 @@
-bool LTS =
-    word(mesh.ddtScheme("ddt(rho)"))
- == fv::localEulerDdtScheme<scalar>::typeName;
-
-tmp<volScalarField> trDeltaT;
-
-if (LTS)
-{
-    Info<< "Using LTS" << endl;
-
-    trDeltaT = tmp<volScalarField>
-    (
-        new volScalarField
-        (
-            IOobject
-            (
-                "rDeltaT",
-                runTime.timeName(),
-                mesh,
-                IOobject::READ_IF_PRESENT,
-                IOobject::AUTO_WRITE
-            ),
-            mesh,
-            dimensionedScalar("one", dimless/dimTime, 1),
-            zeroGradientFvPatchScalarField::typeName
-        )
-    );
-}

applications/solvers/compressible/rhoCentralFoam/setRDeltaT.H

@@ -15,7 +15,7 @@
     (
         1/dimensionedScalar("maxDeltaT", dimTime, maxDeltaT),
         fvc::surfaceSum(amaxSf)().dimensionedInternalField()
-       /(2*maxCo*mesh.V())
+       /((2*maxCo)*mesh.V())
     );
 
     // Update tho boundary values of the reciprocal time-step