When a finite-area case could not find an entry for "lnGradSchemes"
in the "faSchemes" file, the "corrected" scheme has been picked up
by default. Therefore, any changes in "snGradSchemes" entry will not
be read by finite-area models.
- adjust surfactantFoam/planeTransport tutorial to have partial
coverage of the plate by the finiteArea mesh.
Depending on the decomposition, the outflow boundary may coincide
with a processor patch (good for testing purposes).
- additional Allrun-parallel versions for targetted future behaviour
