Doc: eww-prompt-history

[T.V Raman]

The variable eww-prompt-history appears to track urls even if
url-history-track is set to nil, which is jarring.

Also, that var --- eww-prompt-history --- could do with some
documentation and tips on how to decide what urls end up in that list.

-- 

Thanks,

--Raman(I Search, I Find, I Misplace, I Research)
♉ Id: kg:/m/0285kf1  🦮

--

Thanks,

--Raman(I Search, I Find, I Misplace, I Research)
♉ Id: kg:/m/0285kf1  🦮