DJGPP specific issues.

DJGPP specific issues.
* djgpp/config.bat: Add filenames that are not 8.3 clean and that must
be changed.  Copyright timestamp adjusted.
* djgpp/config.sed: Add filenames that are not 8.3 clean and that must
be changed.  Copyright timestamp adjusted.
* djgpp/config.site: Copyright timestamp adjusted.
* djgpp/config_h.sed: Copyright timestamp adjusted.
* djgpp/djunpack.bat: Copyright timestamp adjusted.
* djgpp/fnchnage.lst: Add filenames that are not 8.3 clean to the
filename translation list.
* djgpp/subpipe.c (init_subpipe): Check the environment variables
TMPDIR, TMP and TEMP, in that order, to determinate where the temp
files shall be created.  Before trying to use the temp dir where the
environment variable points to check that the dir really exists. If
not default to the cwd as temp dir.  Copyright timestamp adjusted.
* djgpp/subpipe.h: Copyright timestamp adjusted.
* djgpp/testsuite.sed: Copyright timestamp adjusted.