add cparsons and bttk to the CONTRIBUTORS file

CONTRIBUTORS

diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index fed38b9..a3eeb5b 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -11,8 +11,10 @@
 
 Tony Allevato <allevato@google.com>
 Jon Brandvein <brandjon@google.com>
-Nathan Herring <nherring@google.com>
-Laurent Le Brun <laurentlb@google.com>
+bttk <bttk@google.com>
+Chris Parsons <cparsons@google.com>
+Dave MacLachlan <dmaclach@google.com>
 Dmitry Lomov <dslomov@google.com>
 Jingwen Chen <jingwen@google.com>
-Dave MacLachlan <dmaclach@google.com>
+Laurent Le Brun <laurentlb@google.com>
+Nathan Herring <nherring@google.com>