Add pthatcher@webrtc.org to talk/OWNERS.

pthatcher@ is a new member of the team with good libjingle knowledge.

BUG=
R=juberti@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/9349004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/talk@5636 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/OWNERS b/OWNERS
index ddb55cf..364851b 100644
--- a/OWNERS
+++ b/OWNERS
@@ -5,6 +5,7 @@
 juberti@webrtc.org
 mallinath@webrtc.org
 perkj@webrtc.org
+pthatcher@webrtc.org
 sergeyu@chromium.org
 tommi@webrtc.org
 wu@webrtc.org