- For compatibility, access to the old global names is provided via
  macros
        #define FOAMversion     foamVersion::version
        #define FOAMbuild       foamVersion::build
        #define FOAMbuildArch   foamVersion::buildArch

- this isolation makes it easier to provide additional scoped methods
  for dealing with version related information.  Eg, printBuildInfo()

- Catch any leading option (the incorrect location).
- Catch initialization error for cleaner result.

- 'unfriend' operators on dimensionSet, since they operate without
  requiring access to non-public members.

- add missing invTransform() function for dimensionSet.

- make inv(const dimensionSet&) available as
  operator~(const dimensionSet&), which can be used instead
  of (dimless/ds).

- writing of dictionary entry with the name of the dimensionedType
  suppressed if it is identical to the keyword.
  This corresponds to the input requirements.

- deprecate dimensionedType constructors using an Istream in favour of
  versions accepting a keyword and a dictionary.

  Dictionary entries are almost the exclusive means of read
  constructing a dimensionedType. By construct from the dictionary
  entry instead of doing a lookup() first, we can detect possible
  input errors such as too many tokens as a result of a input syntax
  error.

  Constructing a dimensionedType from a dictionary entry now has
  two forms.

  1.  dimensionedType(key, dims, dict);

      This is the constructor that will normally be used.

      It accepts entries with optional leading names and/or
      dimensions. If the entry contains dimensions, they are
      verified against the expected dimensions and an IOError is
      raised if they do not correspond. On conclusion, checks the
      token stream for any trailing rubbish.

  2.  dimensionedType(key, dict);

      This constructor is used less frequently.

      Similar to the previous description, except that it is initially
      dimensionless. If entry contains dimensions, they are used
      without further verification. The constructor also includes a
      token stream check.

      This constructor is useful when the dimensions are entirely
      defined from the dictionary input, but also when handling
      transition code where the input dimensions are not obvious from
      the source.

      This constructor can also be handy when obtaining values from
      a dictionary without needing to worry about the input dimensions.
      For example,

         Info<< "rho: " << dimensionedScalar("rho", dict).value() << nl;

      This will accept a large range of inputs without hassle.

ENH: consistent handling of dimensionedType for inputs (#1083)

BUG: incorrect Omega dimensions (fixes #2084)

- easier when making modifications

STYLE: spelling in topoSetSource comments

- this seems to be the only reliable means of obtaining the values.

  Using typeName_() yields the wrong value.

  Using the typeName causes initialization issues
  (segfault when executing on some systems).

- support name filtering by class based on <Type> or predicates.
  Eg,

      objects.sortedNames<volScalarField>(namePattern);
  vs  objects.sortedNames(volScalarField::typeName, namePattern);

  These can also be used directly for untyped name matching.
  Eg,
      objects.sortedNames<void>(namePattern);

  Can also use a predicate:

      objects.sortedNames(wordRe("vol.*Field"), namePattern);
      objects.sortedNames
      (
          [](const word& clsName){ return clsName.startsWith("vol"); },
          namePattern
      );

- can be useful for obtaining information about number of fields.
  Eg,

       nScalar = mesh.count<volScalarField>(wordre);

- replace explicit use of wordRe, wordRes, wordHashSet as filters
  with a MatchPredicate.

- support filtering by class based on <Type> or predicates

- naming similar to objectRegistry, with unambiguous resolution.
  The lookup() methods have different return types depending on the
  calling parameter.

STYLE: use IOobjectListTemplates.C for implementations

- previously included as local definition within IOobjectList.C,
  but will be adding more templated methods soon.

- adjust parameters (eg, matchName instead of matcher) to show their
  function

ENH: handle objectRegistry::names<void>(...)

- this is equivalent to no Type restriction, and can be used when
  filtering names. Eg,

     obr.names<void>(wordRe..);

- returns indices of matching entries.

- handle tmp fields in interpolate methods

- special method interpolateInternal() for creating a volume field
  with zero-gradient treatment for patches from an internal field.

  This method was previously also called interpolate(), but that
  masked the ability to subset the internal field only.

  Ensight output needs the volume field:
      uses interpolateInternal().

  VTK output has separate handling of internal and patch fields:
      uses interpolate().

ENH: added fvMeshSubset mesh() method for baseMesh or subMesh.

- simplies coding when the fvMeshSubset may or may not be in active use.

ENH: update foamToEnsight to use newer methods in wrapped form

- static interpolate functions with renaming for manual use with
  fvMeshSubset (when fvMeshSubsetProxy may be too limiting in
  functionality)

- helps reduce clutter in the topoSetDict files.

  Caveats when using this.

  The older specification styles using "name" will conflict with the
  set name. Eg,

    {
        name    f0
        type    faceSet;
        action  add;
        source  patchToFace;
        sourceInfo
        {
            name   inlet;
        }
    }

    would flattened to the following
    {
        name    f0
        type    faceSet;
        action  add;
        source  patchToFace;
        name   inlet;
    }
    which overwrites the "name" used for the faceSet.

    The solution is to use the updated syntax:

    {
        name    f0
        type    faceSet;
        action  add;
        source  patchToFace;
        patch   inlet;
    }

- faceBitSet, pointBitSet and faceBoolSet (similar to cellBitSet)
  * allows topo sources in a wider variety of places.
  * With copy or move constructors.

- cylinderToPoint, searchableSurfaceToFace, searchableSurfaceToPoint,
  sphereToFace, sphereToPoint sources

- optional innerRadius for sphere and cylinder sources to treat as hollow.

- support "sets" as well as "set" for cellToCell, faceToFace... sources.

  * convenience and avoids writing the set during processing.

- now applicable to labelLists.

Note:
  in some situations it will be more efficient to use
  Foam::identity() directly. Eg,

     globalIndex globalCells(mesh.nCells());
     ...
     labelList cellIds
     (
         identity(globalCells.localSize(), globalCells.localStart())
     );

- this helps for trapping unguarded dictionary lookups.

- old 'DELETE' enum was easily confused with 'REMOVE', which removes
  the set, not the elements from the set.

- provide corresponding subtractSet() method

STYLE: HashSet set/unset instead of insert/erase methods in topoSetSource

- simplifies switching to/from bitSet storage

- replaces "centre", using the same keyword as other objects
  (eg, plane, rotatedBox, coordinateSystem etc).

- uses the keywords 'zones' and 'zone' to avoid potential conflicts
  with a named topoSet action, but accepts 'name' for compatibility.

- as part of the cleanup of dictionary access methods (c6520033)
  made the dictionary class single inheritance from IDLList<entry>.

  This eliminates any ambiguities for iterators and allows
  for simple use of range-for looping.

  Eg,
      for (const entry& e : topDict))
      {
          Info<< "entry:" << e.keyword() << " is dict:" << e.isDict() << nl;
      }

   vs

      forAllConstIter(dictionary, topDict, iter))
      {
          Info<< "entry:" << iter().keyword()
              << " is dict:" << iter().isDict() << nl;
      }

- more dictionary-like methods, enforce keyType::LITERAL for all
  lookups to avoid any spurious keyword matching.

- new readEntry, readIfPresent methods

- The get() method replaces the now deprecate lookup() method.

- Deprecate lookupOrFailsafe()
  Failsafe behaviour is now an optional parameter for lookupOrDefault,
  which makes it easier to tailor behaviour at runtime.

- output of the names is now always flatted without line-breaks.
  Thus,

     os << flatOutput(someEnumNames.names()) << nl;
     os << someEnumNames << nl;

  both generate the same output.

- Constructor now uses C-string (const char*) directly instead of
  Foam::word in its initializer_list.

- Remove special enum + initializer_list constructor form since
  it can create unbounded lookup indices.

- Removd old hasEnum, hasName forms that were provided during initial
  transition from NamedEnum.

- Added static_assert on Enum contents to restrict to enum or
  integral values.  Should not likely be using this class to enumerate
  other things since it internally uses an 'int' for its values.

  Changed volumeType accordingly to enumerate on its type (enum),
  not the class itself.