* m4/error.m4: Run AC_FUNC_STRERROR_R. * lib/error.h, lib/error.c: Update.
* m4/prereq.m4, m4/c-bs-a.m4, m4/mbstate.m4: New files, from Fileutils 4.0.27. * src/main.c (printable_version): Remove. * src/lex.c, src/reader.c: Use `quote'. * lib/error.c, lib/error.h: New files, needed by xmalloc.c.