ntpd: update to version 4.2.8p17

Also some spell fixes for README.md

Drop patch-0001 - ntpd >= 4.2.8p16 patched this behaviour. See:

https://bugs.ntp.org/show_bug.cgi?id=3741 (and the linked diff there)
https://git.nwtime.org/websites/ntpwww/commit/d2a7faef2fea5f10b28cc2ee1d842e4b241f414f



Signed-off-by: Paul Donald <newtwen@gmail.com>