* Makefile.am: DJGPP specific files added to EXTRA_DIST.

* Makefile.am: DJGPP specific files added to EXTRA_DIST.
* djgpp/Makefile.maint: Fix PACKAGE variable computation.
* djgpp/config.bat: Replace every occurence of the file name
scan-gram-c.c with c-scan-gram.c. The same for scan-skel-c.c with
c-scan-skel.c to conform with the 8.3 file name restriction on MSDOS.
* djgpp/config.sed: Replace every occurence of the file name
scan-gram-c.c with c-scan-gram.c. The same for scan-skel-c.c with
c-scan-skel.c to conform with the 8.3 file name restriction on MSDOS.
* djgpp/djunpack.bat: DJGPP specific file.
* djgpp/fnchange.lst: DJGPP specific file.
* djgpp/README.in: Add new information about how to unpack the bison
source on MSDOS and other systems which have 8.3 file name restrictions
using djunpack.bat and fnchange.lst.