Updated strings to v4.0.0
@@ -3,4 +3,4 @@ from cleverhans.devtools.version import append_dev_version
# If possible attach a hex digest to the version string to keep track of
# changes in the development branch
-__version__ = append_dev_version('3.0.1')
+__version__ = append_dev_version('4.0.0')
