Conflicts:
	applications/utilities/surface/surfaceCheck/surfaceCheck.C

- Write the individual contents, without a surrounding 'boundaryField'
  block. Similar to what dictionary::writeEntries() offers.

- Can currently have a periodic restart, but for simulations with a
  known run-up, it can be useful to have a specific time to restart
  the averaging.

- Note that the restartTime acts as a 'single-shot'. If the
  restartTime is already in the past when a simulation is started, it
  is ignored. If, during a simulation, the restartTime is crossed, it
  will be triggered and then set itself to be ignored in the future.

- On the first call, ParaView_DIR is unset and thus the clean-path
  fails with the warning "ParaView_DIR: Undefined variable."

  This looks messy, but is of no _major_ consequence since paraview
  doesn't need to be removed anyhow. The only slight risk is that the
  path to a third-party cmake might not be cleaned.

- Patch as per Bruno's suggestion.

- It is incorrect to prefix the assignment with an 'export' since this
  automatically marks the overall command as successful and circumvents
  the fallback.

  There is no simple way to have proper behaviour when sourced with a
  local directory path, but at least it now uses the fallback.

  It is still easy to wreak the mechanism with valid but confusing input.
  For example,

     ". /path/to/openfoam/etc/././bashrc"

  The only real certainty is that "${BASH_SOURCE%/*}"
  should point to the 'etc/' directory. In which case,

      cd ${BASH_SOURCE%/*}    # <- now in the etc/ directory
      pwd=$(pwd -P)           # <- fully-qualified path to etc/
      pwd=${pwd%/*/*}         # <- up two parent levels

  - This works with ". ./bashrc", but fails with ". bashrc"
    (probably not so common).
  - Con: The construct requires an additional sub-shell.

- include cleanup of other postProcessing directories:
  * Ensight, EnSight, ensightWrite

- don't need to remove files that cleanSnappyFiles already removed:
  * 0/cellLevel 0/pointLevel

- bundle removal of constant/ items together:
  * constant/cellDecomposition constant/polyMesh constant/tetDualMesh

correct case re-start