* backtrace.c, backtrace.h, debug.c, debug.h, eq.c,

* backtrace.c, backtrace.h, debug.c, debug.h, eq.c,
gdb_interface.h, gdbint.c, gdbint.h, gh_data.c, gh_init.c,
gh_io.c, gh_list.c, gh_predicates.c, gh_test_c.c, gh_test_repl.c,
init.c, net_db.c, options.c, options.h, ports.c, print.c, read.c,
script.h, snarf.h, srcprop.c, srcprop.h, stacks.c, stacks.h,
throw.c: Update copyright years; these files have been worked on
significantly in 1997, but only had copyright years for 1996.
Also, change name of copyright holder on some from Mikael
Djurfeldt to Free Software Foundation; he has signed papers
assigning the changes to the FSF.