busybox

ntpd: relicense ntpd applet to ISC-style license

OpenNTPd is licensed under ISC-style license so it's good idea to keep
ntpd applet under same license to avoid mess, instead of having
our changes to be under GPL.

Names of original code's authors are added.

Signed-off-by: Adam Tkac <vonsch@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>