[luau] getting system time in milisecs

[Ray Strode]

>
>
>I'm pretty sure in a C class we once used something like x=time(0).  It
>might require time.h or clock.h or something.  But that was a long time ago.
>
time() returns seconds, so i don't think it's precise enough for him. 
 As an aside, time() takes a pointer
so (imo) it's better to use NULL instead of 0 (Unless of course you are 
using C++), or time(&x) will
work, too.

--Ray