* acconfig.h
* configure.in
* app/main.c: added check for putenv and #ifdefed it's usage since NeXTStep is
lame

* libgimp/gimp.c
* app/main.c
* app/plug_in.c: conditionally compile shared mem stuff so platforms without
it can still work

* plug-ins/CEL/CEL.c
* plug-ins/palette/palette.c
* plug-ins/print/print-escp2.c
* plug-ins/print/print-pcl.c
* plug-ins/print/print-ps.c: s/strdup/g_strdup/ for portability

-Yosh