* clients.conf ([DEFAULT]/checker): Update to new default value.
* mandos (Client.start_checker): Bug fix: OSError, not subprocess.OSError. (main): Use "fping -q -- %(host)s" instead of "fping -q -- %%(host)s" as default value for "checker". Always redirect stdin to be from /dev/null, even if in debug mode.
* mandos-clients.conf.xml (DESCRIPTION): Improved wording and refer to the EXPANSION section. (OPTIONS): Added synopsis and improved wording for "checker", "fingerprint", and "secret". Refer to the RUNTIME EXPANSION section for the "checker" option. (EXAMPLE): Update to new default value for "checker".
* mandos-keygen (trap): Split lines and add "set +e".