Bump requirements.txt to Ansible 2.4.1

requirements.txt

@@ -1,6 +1,6 @@
 # Versions are pinned to prevent pypi releases arbitrarily breaking
 # tests with new APIs/semantics. We want to update versions deliberately.
-ansible==2.4.0.0
+ansible==2.4.1.0
 boto==2.34.0
 click==6.7
 pyOpenSSL==16.2.0