Implemented the rest of the methods except for GetKillSwitchStatus

Change-Id: Ia5b1a1c44c2e52653b9845ecc9557f525e6d41b1
diff --git a/api_proto/kill_switch.proto b/api_proto/kill_switch.proto
index 38b688c..9b2f450 100644
--- a/api_proto/kill_switch.proto
+++ b/api_proto/kill_switch.proto
@@ -67,7 +67,7 @@
 }
 
 message ListAuthorizedUsersResponse {
-  KillSwitchAuthorizedUser authorized_users = 1;
+  repeated KillSwitchAuthorizedUser users = 1;
 }
 
 message AddAuthorizedUserRequest {