Adding my name (Leo Dirac) to contributors list.

CONTRIBUTORS.txt

@@ -96,3 +96,4 @@ Jude Nagurney, 2012/06/09
 Jonatan Heyman, 2012/06/10
 David Miller 2012/06/11
 Matthew Morrison, 2012/06/11
+Leo Dirac, 2012/06/11