wrmo: Add -a/-all/all option to remove .o files from all platforms rather than just the current platform.

Description
    Remove all .o files from the object directory tree corresponding to the
    current source derectory or remove only the .o file corresponding to the
    optionally specified [file].

Remove all .dep files from the object directory tree corresponding to the
current source derectory or remove only the .dep files referring to the
optionally specified [file].

This reverts commit c5bea524.

This reverts commit 2e1e671d.

- Also adjusted formatting of usage to match what argList generates

  - send error messages to stderr
  - added -h/-help options where some were missing
  - changed 3-space to 4-space indentation
  - where possible, allow multiple directories from the command-line

  - removed legacy foamDiffSourceList, foamPackChanged
  - added foamPackDoxygen for separate distribution of docs
    handles -prefix option
  - misc. cosmetic changes