Add identity team to OWNERS

Test: None

Change-Id: I75b60dffa56807e8a2c1dcbe2de3187c8e9f8458
diff --git a/user/OWNERS b/user/OWNERS
new file mode 100644
index 0000000..4e8ed97
--- /dev/null
+++ b/user/OWNERS
@@ -0,0 +1,4 @@
+# Library owners
+ahugh@google.com
+jovanak@google.com
+yizheng@google.com