- reflects updates for List, globalIndex handling etc

- using the proximityRegions filter when there is no enclosing surface
  to segregate domains causes a surface of zero-faces to be created.

  In most cases, this means that a simpler proximityFaces filter would
  have been more appropriate. To increase overall robustness, revert
  to the simpler proximityFaces filter logic when the proximityRegions
  would otherwise result in zero faces (globally seen).

- reuse single component buffer within an Ensight output method.
  Use direct UPstream read/write to avoid Pstream char buffers

- replace blocking transfer with scheduled for Ensight cloud output

- use the new updates to globalIndex to manage the bookkeeping

- UPstream::mpiGather (MPI_Gather)   - used by Pstream::listGatherValues
- UPstream::mpiScatter (MPI_Scatter) - used by Pstream::listScatterValues

  These are much simpler forms for gather/scatter of fixed-sized
  contiguous types data types (eg, primitives, simple pairs etc).

  In the gather form, creates a list of gathered values on the master
  process. The subranks have a list size of zero.

  Similarly, scatter will distribute a list of values to single values
  on each process.

  Instead of

      labelList sendSizes(Pstream::nProcs());
      sendSizes[Pstream::myProcNo()] = sendData.size();
      Pstream::gatherList(sendSizes);

  Can write

      const labelList sendSizes
      (
          UPstream::listGatherValues<label>(sendData.size())
      );

  // Less code, lower overhead and list can be const.

  For scattering an individual value only,
  instead of

      labelList someValues;
      if (Pstream::master()) someValues = ...;

      Pstream::gatherList(sendSizes);
      const label localValue
      (
          someValues[Pstream::myProcNo()]
      );

  Can write

      labelList someValues;
      if (Pstream::master()) someValues = ...;

      Pstream::gatherList(sendSizes);
      const label localValue
      (
          UPstream::listScatterValues<label>(someValues)
      );

   Can of course also mix listGatherValues to assemble a list on master
   and use Pstream::scatterList to distribute.

ENH: adjusted globalIndex gather methods

- added mpiGather() method [contiguous data only] using MPI_Gatherv

- respect localSize if gathering master data to ensure that a
  request for 0 master elements is properly handled.

- Pstreams can be ascii/binary but are always currentVersion

- rename UIPstream externalBuf_ to 'recvBuf_' for similar naming as
  PstreamBuffers and symmetry with UOPstream::sendBuf_

- specific enum size for commsType (for more compact structures in the
  future). Default construct lists items.

BUG: possible incidental indexing in UIPstream::read(char*, std::streamsize)

- raw reading had been split into beginRawRead(), readRaw().
  However, this could change the current input position (due to word
  boundary alignment), even if the expected count is zero. Make a
  no-op for count == 0. This mirrors UOPstream::write behaviour.

- construct or reset from a list of local sizes. It is generally
  easier and safer to assemble sizes and let globalIndex determine the
  corresponding offsets, when working with raw values.

- Can use reset() from sizes or fine-tune offsets with setLocalSize()
  instead of using the potentially more fragile non-const access to
  the offsets.

- add globalIndex const_iterator to iterate across the access ranges.
  This is makes it simpler to use with the List slice() method to
  access or operate on a sub-section of list.

  For example,
      scalarField allValues = ...;
      globalIndex procAccess = ...;

      for (const labelRange& range : procAccess)
      {
          someOutput(allValues.slice(range));
      }

- the size of a List often requires adjustment prior to an operation,
  but old values (if any) are not of interest and will be overwritten.

  In these cases can use the _nocopy versions to avoid additional memory
  overhead of the intermediate list and the copy/move overhead of
  retaining the old values (that we will subsequently discard anyhow).

  No equivalent for PtrList/UPtrList - this would be too fragile.

- add swap DynamicField with DynamicList

BUG: fixed Dynamic{Field,List} setCapacity corner case

- for the case when the newly requested capacity coincides with the
  current addressable size, the resize of the underlying list would have
  been bypassed - ie, the real capacity was not actually changed.

- remove (unused) PtrDynList setCapacity method as too fragile

- previously returned the range slice as a UList,
  but this prevents convenient assignment.
  Apply similar handling for Field/SubField

  Allows the following

     labelRange range(...);
     fullList.slice(range) = identity(range.size());

  and

     fullList.slice(range) = UIndirectList<T>(other, addr);

ENH: create SubList from full FixedList (simplifies interface)

- allow default constructed SubList. Use shallowCopy to 'reset' later

- simply adds in the reinterpret_cast, which simplifies coding for
  binary data movement.
  Name complements the size_bytes() method for contiguous data

STYLE: container IO.C files into main headers for better visibility

STYLE: include CompactListList.H in polyTopoChange

- avoids future mismatches if the CompactListList template signature
  changes

GIT: relocate CompactListList into CompactLists/ directory

- useSubMesh() - name as per fvMeshSubsetProxy.
  Setter methods take a parameter instead of direct access.

 - encapsulates toggling

STYLE: noexcept for some Time methods

- previously used an indirect patch to get the sampling locations,
  but this doesn't take account of the face flips. Now use
  the faceZone intrinsic for generating a properly flipped patch
  and provide the sampling locations separately.

STYLE: adjust compatiblity header for surfaceMeshWriter

- it is now possible to include the selected mpi version in the
  top-level bashrc or prefs.sh file. For example,

      WM_MPLIB=OPENMPI-4.1.1  or  WM_MPLIB=openmpi-4.1.1

  after evaluation of the config.sh/mpi, this will define

      WM_MPLIB=OPENMPI-4.1.1  and  FOAM_MPI=openmpi-4.1.1

  During the wmake, the mpi-rules will first load the MPI 'family'
  rules (OPENMPI in this example) before trying to load
  version-specific rules if they exist.

  NOTE: the regular user-defined prefs system is unaffected by this
  change. This means it is still possible to use a file such as
  'prefs.openmpi' to define the preferred version instead or as well.
  However, it does mean inconsistent naming can be specified.
  For example, specify WM_MPLIB=OPENMPI-4.1.1 at the top-level but
  actually have FOAM_MPI=openmpi-4.0.6 in the prefs.openmpi file.
  This will make the value of WM_MPLIB misleading.

CONFIG: foamConfigurePaths support for sys-openmpi major version

CONFIG: cleanup any shadow env variables

ENH: Regroup and unify various virtual functions in laminar/RAS/LES models

See merge request !487

ENH: LESeddyViscosity: move Ce to LESModel to
enable omega/epsilon virtual hierarchy

- migrate to c++14 for most compilers *except* gcc.
  There are still many systems in use with gcc-4.8.5, which does not
  support c++14.

- initial rules for nvidia compilers (pgi is will soon be defunct).
  Not fully tested...

CONFIG: provide fallback value for the user directory name

- in containers may have an unset USER env variable.
  Default to 'user' to prevent ugly looking directory names.

ENH: decomposePar: cyclicAMI in constraints. Fixes #2242

See merge request !491

- supports redistributePar -decompose -fileHandler collated
- supports redistributePar -reconstruct
- does not support redistributePar with collated in redistribution mode

- added contact resistance to turbulentTemperatureCoupledBaffleMixed
- added basic multi-world to turbulentTemperatureRadCoupledMixed
- added unit-testcase to $FOAM_APP/test/multiWorld

- noticed by Robin Knowles with `decomposePar -fields -copyZero`

  The internals for the Foam:cp method combine the behaviour of
  a regular `cp` and `cp -R` combined.

  When source and target are both directories, the old implementation
  created a subdirectory for the contents.
  This normally fine,

      ok:  cp "path1/0/" to "path2/1" -> "path2/1/2"
      BUT: cp "path1/0/" to "path2/0" -> "path2/0/0" !!

  Now add check for the basenames first.
  If they are identical, we probably meant to copy directory contents
  only, without the additional subdir layer.

BUG: decomposePar -fields -copyZero copies the wrong directory

- was using the current time name (usually latest) instead of copying
  the 0 directory

ENH: accept 0.orig directories as a fallback to copy if the 0 directory
is missing

- simplfies differences for OSX

- use orte-info to determine prefix/libdir for openmpi.
  This removes a run-time dependency on mpicc, which is actually
  only needed for building with MPI (not running with MPI).
  The corresponding openmpi devel package (deb/rpm) will not
  necessarily be installed on a particular system.

- retain mpicc logic if the new logic using orte-info does not
  deliver an answer. Final fallback to using 'orterun' to
  infer prefix/libdir.

- Additional logic for intel and msmpi to make it easier to
  locate these vendor packages within ThirdParty
  (ie, under ThirdParty/opt/...)

CONFIG: improve robustness

- add check for absolute path when adding PATH/LD_LIBRARY_PATH etc.

- prefix more variables with '_foam*' to prevent accidental overwrite
  of userspace shell variables when sourcing

- avoid deprecated autoPtr check

- bundle bool values in fvPatchField for compacter allocation

- change useImplicit to a set method taking an argument instead of
  allowing direct access.

ENH: adjust fileName component method

- the location \c npos returns the last component

BUG: incorrect addressing in rcEdge, but not used in the code.

- top-level faceCells() on the boundary list simplifies the creation
  of lduAddressing etc, can also be useful on its own

STYLE: replace isA/refCast combination with a single isA