Removed some non-ANSI-C strftime format strings ("%F") and
locale-dependent formats ("%c") from NSE scripts and libraries.
C99-specified %F was noticed by Alex Weber
(http://seclists.org/nmap-dev/2013/q2/300)
sending the second probe if the first caused an error. This is based on
the results of a test by Richard Sammet showing that the default timeout
of 30 s is too long when scanning many open|filtered ports that are in
fact filtered.