Add codereview.settings file

Change-Id: I8c2afbc4f80205d15de0c18eee5b12a6ba25e2e0
Reviewed-on: https://gn-review.googlesource.com/2400
Reviewed-by: Petr Hosek <phosek@google.com>

codereview.settings

diff --git a/codereview.settings b/codereview.settings
new file mode 100644
index 0000000..22f8b55
--- /dev/null
+++ b/codereview.settings
@@ -0,0 +1,2 @@
+PROJECT: gn
+GERRIT_HOST: True