- regression as a result of changed time-handling from #1418.
  Now cache the fields information internally.

- previously allowed mapped value modification with a const iterator.
  However, this can lead to incorrect access patterns.

  Now tie the constness of the mapped value to that of the iterator.

- Remove deprecated iterator object() method.
  Was only used internally and was superseded by the val() method
  in an earlier version.

ENH: change isPointer to isPointerLike

- can distinguish between real pointers and wrapped pointers

- this largely reverts 3f0f218d and 4ee65d12.

  Consistent addressing with support for wrapped pointer types (eg,
  autoPtr, std::unique_ptr) has proven to be less robust than desired.
  Thus rescind HashTable iterator '->' dereferencing (from APR-2019).

- for special cases when normal writing is to be completely disabled
  and replaced with alternate means (eg, via a function object).

- support "adjustable" as "adjustableRunTime" alias to reduce typing
  for writeControl or outputControl

- use HashTable emplace instead of insert to avoid unneeded argument
  (for HashSet).

- use emplace when generating zero-initialized values for
  HashTable::operator()

- drop unused parameter from Detail::HashTableSingle,
  adjust templates parameter names

- forward HashTable::operator[] to the semantically identical
  HashTable::at() to avoid code duplication

- generated C++ files, but didn't use C++ compiler

- call also be used non-interactively for simple 'one-shot' use of
  OpenFOAM utilities or solvers

STYLE: use dash instead of brackets for '- see www.OpenFOAM.com'

- less cluttered in combination with API information

- makes the intention clearer, allows for future tightening of
  iterator access rules.

- useful for manual handling of string with comments

Does not fix the tolerance issue.

- now maintains a correct list of geometry instances, without assuming
  contiguous file numbering. However, if the numbering is contiguous,
  the more compact case representation will be used.

- an advanced feature, for example when sampling on a static patch
  while some motion occurs elsewhere. [use with caution]

- If the sampled surface dictionary is modified during run-time, the
  ensight file indexing for the geometry will become out of sync.
  This is addressed in a subsequent commit.

- this can be useful for preloading of libraries, or for utilities
  that don't use system/controlDict.

  The additional libraries can be specified individually:

      myUtil -lib lib1 -lib lib2 -lib lib3

  When specified like this, the options add up.

  Or as a 'captured' list using OpenFOAM's standard arg list handling:

      myUtil -lib '(' lib1  lib2 lib3 ')'
      myUtil -lib \( lib1  lib2 lib3 \)

  or as single argument list:

      myUtil -lib '("lib1" "lib2" "lib3")'

  When specified as a single argument, would normally take advantage
  of the transparent handling of word vs fileName and omit the string
  quotes:

      myUtil -lib '(lib1 lib2 lib3)'

ENH: dlOpen error messages now propagated into dlLibraryTable

- this makes the context more relevant and also avoids the previous
  annoyance of double warnings (one from the POSIX loader, and one
  from dlLibraryTable)

STYLE: mark -noFunctionObjects and -withFunctionObjects as 'advanced'

- reduces clutter. Still visible with -help-full