External coupled

Improvements and bugfixes for externalCoupledFunctionObject - issues #278 #269

See merge request !72

BUG: resolve some decomposeParDict problems (issues #60, #265).

- Cleanup/centralize handling of -decomposeParDict by relocating
  common code into argList. Ensures that all processes receive
  identical information about the -decomposeParDict opton.

- Only use alternative decomposeParDict for simpleFoam/motorBike
  tutorial so that this will be included in the test loop for snappy.

- Added Mattijs' fix for surfaceRedistributePar.

See merge request !73

- In the corner case with few faces or points, the normal List I/O
  results in a compact list representation.

  This is less than desirable for external programs with simple
  line-based parsers.

- Write exactly the following

*Faces*
// Patch: <word-Region> <word-Patch>
<int-nFaces>
(
<int-faceSize>(<int> .. <int>)
...
)

*Points*
// Patch: <word-Region> <word-Patch>
<int-nPoints>
(
(<float-x> <float-y> <float-z>)
...
)

STYLE: only use serial form of createExternalCoupledPatchGeometry in tutorial

- less confusing for the user, who wonders why it is being done twice.

Adding clone member functions to motion solvers

- Cleanup/centralize handling of -decomposeParDict by relocating
  common code into argList. Ensures that all processes receive
  identical information about the -decomposeParDict opton.

- Only use alternative decomposeParDict for simpleFoam/motorBike
  tutorial so that this will be included in the test loop for snappy.

- Added Mattijs' fix for surfaceRedistributePar.

- Also fixed bug noted in issue #269

- Previous implementation had all faces together, which made
  it difficult (impossible) for external applications to
  figure out which geometry was being referred to.

- Provide separate region/patches as follows:

    // Patch: <regionName> <patchName>

  For example,

    // Group: coupleGroup
    // Patch: heater minY
    8( ... )

  The region-name is always present, even if there is only one region.

- This change is a partial reversion to the behaviour in 2.4.x, except
  that we can now also handle multi-region geometries.

  Changing the leading comment from "# " to "// " facilitates parsing
  of the files with OpenFOAM itself if necessary.

- This provides a mechanism for the external code to detect when
  OpenFOAM is done.

- Adjust tutorial to use the mechanism. Also test in parallel.

- A preliminary minor adjustment only.

- Can occur with some user names, or mounted paths.
  Resolve by using '?' for the separation character.

  Since '?' is a shell-glob, it is highly unlikely to occur appear in
  filenames.  Additionally, it is not a meta-character in standard sed,
  nor in the GNU extension (which uses '\?').

- Superfluous #include "FieldFunctions.H" provokes warnings/errors
  with newer gcc.

changed flag which caused infinite while loop. Background info:
- findCellZoneTopo tries to find for all named surface intersections
which side of the face is in the faceZone
- i.e. it tries to make the cellZone consistent with the faceZone
(to fix small problems)
- this had some logic to assign the neighbour cellZone to the owner cellZone
- which didn't check for the neighbour being the same value as the owner
- but still set a 'changed' flag which caused the loop to never end.

ENH: wallDist - added option to evaluate every XXX steps

Added functionality to update the wall distance every XXX steps

Note: only applies to movePoints() - topology change bypasses the update interval and triggers a re-calculation
Syntax:
```
wallDist
{
    method          ...
    updateInterval 5; // optional - default is 1
}
```

Test case: [mixerVesselAMI2D.tgz](/uploads/c0bee1decc0337018272f3566b6a4416/mixerVesselAMI2D.tgz)

See merge request !62

All of the access methods for autoPtr include validity checks and will
fail if the underlying point is NULL. In some cases, however, we'd
like to retain the automatic deletion mechanism, but still address a
nullptr. This is mostly for cases in which a file-stream should be
allocated, but only on the master process. For these cases we'd still
like to pass through and reference the underlying pointer (eg, to
obtain the correct method call) without tripping the pointer check
mechanism. If we attempt to use the ptr() method, the autoPtr memory
management is bypassed and we risk memory leaks.

Instead provide an alternative mechanism to obtain the raw underlying
pointers/references. Use rawPtr() and rawRef() for these potentially
useful, but also potentially dangerous, operations.

- Normally use '()' to deference. This has extra safety and issues a
  fatal error if the underlying pointer is not valid.

  However, in some cases we are happy with getting a null reference.
  The refOrNull() method returns the reference without any checking.

  Usage example:

      autoPtr<OFstream> osPtr;
      if (Pstream::master())
      {
          osPtr.reset(new OFstream(...));
      }
      writeViaMaster(osPtr.refOrNull());

      - The writeViaMaster() call takes an OFstream reference,
        but this is only used directly on the master.
        The slaves will pass things through to the master.

- can be used to loop over all enumerations in the order of definition.

- Similar to ensight converters (issue #240),
  improve speed for detection of lagrangian clouds.

- provide a -noLagrangian option for symmetry

- Less looping when detecting lagrangian clouds and their fields.

- Avoid using Time::setTime() and IOobjectList in tight loops.
  They both kill performance immensely.

ENH: provide a -noLagrangian option to foamToEnsight and foamToEnsightParts
for even more control.

- More informative than a horizonal line, can help when debugging.

STYLE: remove unused write field methods from ensightParts