Feature paraview vtk

See merge request !116

- Requires (1L << N) instead of (1 << N), otherwise it overflows
  and the result is zero.

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.

- as per foamToEnsight, foamToEnsightParts.
  Allows the user to specify different output directories.

- this should not have been there in the first place

- user-selectable format (vtk or vtu, ascii or binary)
- dictionary syntax closer to ensightWrite
- tutorial example in windAroundBuildings

- eliminates the PtrList requirement (more flexible)

- eliminates the PtrList requirement (more flexible)

COMP: use tmp intermediate for volPointInterpolation return value

- gcc 4.8.5 had some weird issue of otherwise not binding a const-ref.
  (in foamVtkInternalWriterTemplates.C)

- elminate the foamVtkFormatter operator() in favour of xmlAttr.
  Improves readability and the purpose is clearer.

- Use on/off vs longer compressed/uncompressed.
  For consistency, replaced yes/no with on/off.

- Avoid the combination of binary/compressed,
  which is disallowed and provokes a warning anyhow

fanPressureFvPatchScalarField.H:  Correcting header documentation
RAS/TJunctionFan/0.orig: Creating tutorial for fanPressure
Adding pRef and pValue for tutorial createZeroDirectory/snappyMultiRegionHeater

Adding intertial term switch to solarLoad chtMultiRegionFoam case

- By definition, binary STL uses float (not double) when reading.
  The ascii STL should be the same. This reduces memory overhead when
  loading files. The older triSurface reader had float, the surfMesh
  reader had double, but now has float.

- Inconsistency in the STL merge-tolerances between triSurface reader,
  surfMesh reader and WM_SP vs WM_DP. Now use consistent tolerances
  conrresponding to 10,100 * doubleSMALL.

- Similar float/double code adjustments for TRI format since this is
  very similar to the STL reader and had a similar inconsistency between
  the triSurface and surfMesh version. The AC3D reader still uses
  double when reading, but this can be revisited in the future (and can
  then remove the stichTriangles method too).

- only treat text as an option if it is preceded by 0-4 spaces.
  This prevents the description of an option from being accidentally
  detected as an option.

- can avoid the intermediate point distance field in exchange for
  calculating a point subtraction twice.