- foamCleanPath now only splits the environment variable on ':', which
  allows other directories with spaces or '(..)' etc to pass through
  without major issue.

- The filter arguments are split on whitespace, colons or semi-colons.

- since 1612, FOAM_INST_DIR and foamInstDir longer have any
  special meanings when sourcing the bashrc or cshrc files.
  Thus no need for special treatment in any of the dispatch wrappers.

  Retained FOAM_INST_DIR as (unexported) variable in etc/bashrc,
  just in case people are using patched versions of etc/bashrc
  as part of their installation.

ENH: relax prefix restrictions on foamCreateVideo (issue #904)

- shift the implicit '.' to be part of the default prefix. This allows
  things like "-image myimages_00" to work as might be expected.

- add some notes about 'git submodule' in modules/README.md

- adjust comment formatting to reduce clutter

- relocate WM_COMPILER_ARCH, WM_COMPILER_LIB_ARCH from
  etc/{bashrc,cshrc} to etc/config.{csh,sh}/settings since these
  should not be changed by the user anyhow.

- Use gcc/g++ as common base and specialize afterwards (to reduce
  duplication)

- adjust format of WM_PROJECT_SITE fallback to allow for easier
  automated edits

- easier to ensure that flags are consistent

- primary points for an external user are the polyMesh constructor

- add config info for gcc-7.3.0

COMP: intel-2017. Ignore unknown pragmas. Disambiguate method resolution.

- forward command-line arguments for paraview, where they may also be
  evaluated (cshrc, POSIX shell)
  Eg,
      . etc/bashrc ParaView_VERSION=5.4.1-mpipy
      source etc/cshrc ParaView_VERSION=5.4.1-mpipy

- export library path for gmp/mpfr from CGAL config files.
  This is required when non-system gmp/mpfr libraries are being
  used, but not using a ThirdParty compiler installation.

- automatically handle lib/ vs lib64/ (eg, for central installations)
  for packages such as boost, CGAL, etc. While the ThirdParty
  compilation of these will normally land in lib64/, this may not be
  the case when they are supplied by another means.

- reworked the handling of foamEtcFile and foamCleanPath for less
  clutter in the configuration files.
  Added the bin/tools/lib-dir script to handle logic that is
  too complex to easily manage in csh.

- this avoids a situation when an aborted sourcing of the etc/bashrc
  file can leave WM_SHELL_FUNCTIONS defined, which causes all
  subsequent sourcing to fail.

- FOAM_CONFIG_NOUSER
  Suppress use of user/group configuration files.
  This is useful when packaging for a central installation.

- allow additional user tuning of compiler settings.
  Per-compiler overrides in "compiler-$WM_COMPILER" files

- for Darwin, mention that clang is the only compiler configured

- adjust comments

- the (global) associative array requires bash >= 4.2

- the cray C/C++ compilers appear to be option-compatible with gcc.

- no wmake rules for 32bit builds (deemed to be unnecessary)

- use complete -o filenames, dropped -o nospace to make it more responsive.

- restructure completion code to use a unified backend, which makes it easier
  understand, maintain and re-use.

- foamCreateBashCompletions now simply outputs to a stdout, and allows
  quick generation of completion of single applications.

- add -fileHandler completion in anticipation of future changes there.

- relocated as etc/config.s/bash_completion to prevent inadvertently
  having two versions (.com, .org) installed at the same time.

- allows configuration without an environment variable.
  For compatibility still respect FOAM_SIGFPE and FOAM_SETNAN
  env-variables

- The env-variables are now treated as true/false switch values.
  Previously there was just a check for env exists or not, but this
  can be fairly fragile for a user's environment.

- minor cleanup of bash completion script

- suppress error messages that appear with zsh.
  According to unset(1p), 'unset -f' unsets a function.
  If the function was not previously defined, this is a no-op.
  This is similar for zsh, but there it emits a warning if the
  function was not previously defined.

- avoid 'local' in functions sources from etc/bashrc.
  ksh does not support this.

- use 'command' shell builtin instead of 'type'.
  Seems to be more consistent between shell flavours.

- this implies that jobControl is a user-resource for OpenFOAM.
  It was previously located under $WM_PROJECT_INST_DIR/jobControl,
  but few users will have write access there.

- an unset FOAM_JOB_DIR variable is treated as "~/.OpenFOAM/jobControl",
  which can partially reduce environment clutter.

- provide argList::noJobInfo() to conveniently suppress job-info on an
  individual basis for short-running utilities (eg, foamListTimes) to
  avoid unneeded clutter.

- permit SYSTEMMPI user adjustments via
      etc/config.{csh,sh}/mpi-system
  This can be a convenient place for setting up SYSTEMMPI for OpenFOAM
  without adjusting bashrc, prefs.sh ...

- add a USERMPI type. This represents any generic mpi implementation.
  The user is responsible for supplying an appropriate
  wmake/rules/General/mplibUSERMPI file and managing all settings.

  This type of setup can be useful in combination with specific build
  systems (SPACK, EASYBUILD, etc) or module systems for which the MPI
  variant is part of the installed configuration.

- cleanup variables last in etc/bashrc for a clean exit code

- this allows the sys-admin to provide base values independent of any
  WM_PROJECT_SITE value.

Resolves patch request https://bugs.openfoam.org/view.php?id=2490

- handle sourcing bashrc with a relative path (issue #383)
- handle sourcing from bash and zsh.
  Still need manual intervention when sourcing dash, sh, or ksh.
- replace grep in etc/cshrc with sed only
- logical instead of physical path for WM_PROJECT_DIR (issue #431).
  Doesn't seem to be possible for csh/tcsh.

  * Continue using physical locations when comparing directories,
    but not for the top-level FOAM_INST_DIR, WM_PROJECT_DIR.

- relocate WM_CC, WM_CXX overrides from etc/config.*/compiler
  to etc/config.*/settings to ensure that they are left untouched
  when etc/config.sh/compiler is sourced while making third-party
  packages (eg, gcc, llvm, CGAL).

- provide fallback FOAM_TUTORIALS setting in RunFunctions

STYLE: remove "~OpenFOAM" fallback as being too rare, non-obvious

- easier to test or use different versions

- change WM_CXXFLAGS to -std=c++11 instead of -std=c++0x