- the noOp now returns const reference, noexcept

- improves similarity to autoPtr. Simplifies coding.

  Example,

    tmp<volScalarField> tfield;

    // sometime later...

    tfield.reset
    (
        volScalarField::New("myfield", mesh, dimensionedScalar(Zero))
    );

- as per tmp, disallow tmpNrc assignment from literal nullptr

- as per autoPtr, allow explicit test as bool (same as valid).

Example,

     ($radius > 10) ? sin(degToRad(45)) : cos(degToRad(30))

- protect division and modulo against zero-divide.

- add scanner/parser debugging switches in the namespace,
  selectable as "stringToScalar". For example,

    debug parser:  foamDictionary -debug-switch stringToScalar=2
    debug scanner: foamDictionary -debug-switch stringToScalar=4
    debug both:    foamDictionary -debug-switch stringToScalar=6

- this allows use of #eval results in the tests

- this makes it behave more like other dictionary components.

- can be useful when a scalarField has been used to store booleans and
  we need to recover a bool directly and deal with potential rounding
  issues.

ENH: support "any" as a Switch counterpart to "none"

- now indicate that the dictionary entry is missing, not that it is
  an unknown function type.

STYLE: adjust PatchFunction1New.C to have logic structure look similar

- handle quoted format statement (m4)

- avoids generating a log file, which is missing an "End" tag that
  allows the test loop to identify the completion status

- also use tmp::New forwarding internally

- the full tensor also supports zip/unzip rows/cols
  and unzipRow, unzipCol, unzipDiag

- also support transposed construction when given a set of vectors

- save in META-INFO/build-info for later re-compilation without git.
  This improves tracking beyond simply referring to the the patch level.

  The information is tagged with an underscore to distinguish from
  "real" build information when git is available.

STYLE: improved shell syntax, pushd/popd guards etc.

  - Previously, the default mapping method was `planarInterpolation` which was
    silently suppressed by the default 'interpolate{R,U,L}=false'.

  STYLE: changes:
            `0` to `Zero`,
            `lookupOrDefault` to `getOrDefault`
         improves header documentation

-  make constructors explicit, delete unused constructors

- silently deprecate 'startsWith', 'endsWith' methods
  (added in 2016: 2b143606), in favour of
  'starts_with', 'ends_with' methods, corresponding to C++20 and
  allowing us to cull then in a few years.

- handle single character versions of starts_with, ends_with.

- add single character version of removeEnd and silently deprecate
  removeTrailing which did the same thing.

- drop the const versions of removeRepeated, removeTrailing.
  Unused and with potential confusion.

STYLE: use shrink_to_fit(), erase()