- 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.

- 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.

- lazier evaluation of project name and version based on the directory
  name. Avoids heuristics based on directory names unless really needed.

- cope with alternative directory locations.
  For example, OpenFOAM+VERSION etc.

The combination of the two above appears to be sufficient to open up
the directory naming possibilities.

- additional -list-test option (tests for existence of directory).

FOAM_INST_DIR is the location of the OpenFOAM installation which defaults to
the directory containing the etc/bashrc,cshrc file.  If this default is
not appropriate FOAM_INST_DIR can be set explicitly.

Patches provided by Bruno Santos
Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=231

- use function when sourcing the bashrc to avoid these problems

This reverts commit c5bea524.

This reverts commit 2e1e671d.

- remove all corresponding logic from foamExec

- This lets foamExec use foamEtcFile as well, but debian packaging
  still needs some work

- Also adjusted formatting of usage to match what argList generates

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