- '-c' option (as per shell), '-Dkey[=value]' option to provide
  preferences via the command-line. For example,

      etc/openfoam -DWM_COMPILER=Clang -int64  ./Allwmake -j -s -l

  These can also be combined with other options. Eg,

      etc/openfoam -DWM_COMPILER=Clang \
          -c 'wmake -show-path-cxx -show-cxxflags'

- relocated from bin/tools/ => etc/ for easier access

- bin/tools/openfoam.in : for autoconfig-style installation

- Auto-detect if the shell script was executed with openfoam and
  interpret accordingly.

  Simple example,

      --------------
      #!/usr/bin/openfoam
      cd "${0%/*}" || exit   # Run -*-sh-*- from this dir

      blockMesh
      simpleFoam
      --------------

   Note it is NOT currently possible to provide any other parameters
   this way. Eg,

      `#!/usr/bin/openfoam -sp` (NOT)

   This will either fail to run, or result in infinite recursion.

- skip processing OSspecific/MSwindows since this can cause duplicate
  doxygen entries

STYLE: adjust formatting in code templates

STYLE: use std::string methods without extra qualifications

- when using VTK from ParaView sources it can better to tag them as
  such, but simultaneously not mask the ParaView with hardware
  rendering.

  The additional ParaView_MESA_DIR variable allows this.
  The balance of library and path setup is unaffected by this.

DOC: update doc/BuildIssues

- no stderr redirect needed:
    * 'command -v'

- no stdout/stderr redirect needed:
    * 'rm -f'

STYLE: consistent spacing after redirects

TODO: need to revisit

- relocated BuildIssues.txt -> doc/BuildIssues.md

- reduces installation clutter, allows easier cross-referencing

- remove older deprecated scripts (foamDebugSwitches, foamGraph*)

- was PREFIX/site, now PROJECT/site

  This avoids several issues when installing OpenFOAM in clusters
  without an intermediate OpenFOAM-specific installation prefix.

  The 'site' directory may have a reserved meaning in these situations
  and it is undesirable to 'leak' upwards into the parent directory to
  look for configuration files.

  Placing the default within the project directory avoids this.
  Alternative locations can be given via the WM_PROJECT_SITE variable.

- Prefer the $WM_PROJECT_VERSION from the environment, since this
  is consistent with the foamEtcFile script, and matches better to
  user expectations.

- resolve in favour of "inline explicit", which had marginally more
  uses and provides consistent prefixing for inline methods.

- any code placed here should provide Allwmake and Allwclean scripts
  and normally have compilation targets into FOAM_APPBIN, FOAM_LIBBIN

  Since there is no standardize places for sources or applications,
  a simultaneous build of a module's doxygen documentation requires
  a minor bit of manual effort. Add (via symlink) the sources into
  the modules/doc/ directory to have them included in the normal
  OpenFOAM doxygen documentation generation.

  A makelink.example file is provided there as an example.

- unknown options or missing option values now emit a shorter message
  without the entire usage. This makes it easier to identify the errors
  and is better aligned with the behaviour of GNU system tools.

  ====
     $ simpleFoam -case
     Using: OpenFOAM-plus (see www.OpenFOAM.com)
     Build: plus-01234

     Error: option '-case' requires an argument

     See 'simpleFoam -help' for usage
  ====

- provide for reduced (-help) and full (-help-full) usage information.
  In many cases the reduced usage provided sufficient and easier
  to find the information.

- make -srcDoc an alias for -doc-source

- no warnings about option aliases for future dates.

- the -dir option was added in commit c1c6243c to allow quick
  testing of documentation for a set of classes.
  This was largely replicated in commit 843d83117, but accepting
  multiple directories.

  Apply some of the same ideas here and avoid creation of a tmp file.

- can run doxygen with an alternative Doxyfile, which is useful
  when verifying generated content for particular classes.
  Eg,
      PATH/doc/Allwmake -dir $PWD

- less clutter and typing to use the default template parameter when
  the key is 'word' anyhow.

- use EdgeMap instead of the longhand HashTable version where
  appropriate

'set -x' should be used for debugging.

Added command printing into wmake and Allwmake as a replacement for
'set -x' to log current target.