STYLE: only use paraview settings when actually available
- this means executing makeParaView prior to building OpenFOAM itself,
but is consistent with the instructions given by makeParaView,
and elminates anticipating the source location from the paraview
config file, which increases the build flexibilty for ThirdParty
- Cannot test if these older reader modules actually build,
owning largely to build issues since with paraview 3.14 (Feb 2012)
and paraview 3.98 (Dec 2012) themselves.
etc/config.sh and etc/config.csh
This structure is more convenient to add support for other shells, e.g. zsh, fish etc.
Resolves feature request to simplify support for other shells in
http://www.openfoam.org/mantisbt/view.php?id=1232