man: drop references to removed and obsolete 'systemctl load' command
coredump: display libdw fail string on stack trace fail

- systemd[1]: hello.service: main process exited, code= dumped, status=3/QUIT
- systemd-coredump[2541]: Failed to generate stack trace: Unwinding not supported for this architecture
- systemd-coredump[2541]: Process 1024 (hello) of user 154 dumped core.
dhcp: the localhost isn't valid as hostname either
networkctl: print local domain name in status output