added CONTRIBUTORS

+# CasperJS contributors
+
+```
+$ git shortlog -s -n
+   657  Nicolas Perriault
+    14  Brikou CARRE
+     8  hannyu
+     6  Chris Lorenzo
+     4  pborreli
+     4  nrabinowitz
+     3  Andrew Childs
+     3  Solomon White
+     3  reina.sweet
+     2  Jason Funk
+     2  Michael Geers
+     2  Julien Moulin
+     2  Donovan Hutchinson
+     2  Clochix
+     1  Maisons du monde
+     1  Marcel Duran
+     1  Mathieu Agopian
+     1  Mehdi Kabab
+     1  Mikko Peltonen
+     1  Pascal Borreli
+     1  Rafael
+     1  Rafael Garcia
+     1  Raphaël Benitte
+     1  Andrew de Andrade
+     1  Tim Bunce
+     1  Victor Yap
+     1  alfetopito
+     1  Christophe Benz
+     1  jean-philippe serafin
+     1  Chris Winters
+     1  Jan Pochyla
+     1  Harrison Reiser
+     1  Julian Gruber
+     1  Justine Tunney
+     1  KaroDidi
+     1  Leandro Boscariol
+```
+