Cosmetic changes to ntpviz output

[Paul Theodoropoulos]

I did some copyediting on the output  of ntpviz (some typos, some minor 
rewording). I'm largely a git with regard to git, only knowing the most 
basic commands (I have expert facility with 'git clone').

ESR suggested I perform a 'pull', and request that Gary have a look at 
it. Herewith. I've probably overlooked some other step, but perhaps not.

Thanks.

-- 
Paul Theodoropoulos
www.anastrophe.com