Update readme file to reflect update of TF version.
@@ -75,7 +75,7 @@ pip install -e ./cleverhans
Although CleverHans is likely to work on many other machine configurations, we
currently [test it](https://travis-ci.org/tensorflow/cleverhans) it with Python
-{2.7, 3.5} and TensorFlow {1.4, 1.8} on Ubuntu 14.04.5 LTS (Trusty Tahr).
+{2.7, 3.5} and TensorFlow {1.8, 1.9} on Ubuntu 14.04.5 LTS (Trusty Tahr).
Support for TensorFlow 1.3 and earlier is deprecated. After 2018-11-1 we will
not fix bugs reported for these versions and we will eliminate wrapper code
needed for backwards compatibility with these versions.
