CONTRIBUTORS: three more

R=rsc
https://codereview.appspot.com/7225073
diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 63effd2..73171a9 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -5,6 +5,7 @@
 
 Abhishek Kulkarni <adkulkar@umail.iu.edu>
 Albert Lee <trisk@acm.jhu.edu>
+Alessandro Arzilli <alessandro.arzilli@gmail.com>
 Akshat Kumar <seed@mail.nanosouffle.net>
 André Günther <Andre.G@gmx.de>
 Anthony Martin <ality@pbrane.org>
@@ -28,6 +29,7 @@
 Jeff Sickel <jas@corpus-callosum.com>
 Kris Maglione <jg@suckless.org>
 Marius Eriksen <marius.eriksen@gmail.com>
+Martin Neubauer <m.ne@gmx.net>
 Mathieu Lonjaret <lejatorn@gmail.com>
 Mathieu Lonjaret <mathieu.lonjaret@gmail.com>
 Michael Teichgräber <mt4swm@googlemail.com>
@@ -45,4 +47,4 @@
 Tim Newsham <tim.newsham@gmail.com>
 Tony Lainson <t.lainson@gmail.com>
 Venkatesh Srinivas <extrudedaluminiu@gmail.com>
-
+Xi Wang <xi.wang@gmail.com>