bump version 17.09.0-ce

Signed-off-by: Andrew Hsu <andrewhsu@docker.com>
diff --git a/VERSION b/VERSION
index 025f82b..bec6bec 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-17.09.0-ce-rc3
+17.09.0-ce