Atomic updates

[qznc]

I implemented a D2 version of an open Rosetta problem.

Problem: http://rosettacode.org/wiki/Atomic_updates

Code: http://dpaste.dzfl.pl/e6615a53

Any comments or improvements?

I actually implemented a more scalable version than most of the 
other languages used, by using a lock per item instead of a 
single lock for the whole array.