- handling of dead links (find -L -delete unsupported)
- remove ignore case flag on 's/../../i' used in have_scotch script.
It is unneeded and not tolerated by Darwin's sed.
- avoid embedded comments in EXE_INC (Make/options files), which do
not work well with the OSX LLVM cpp.
It strips out the comments but also removes the continuation char.
STYLE: adjust notes about paraview library locations