Add 'python-memcached' requirement.
@@ -20,6 +20,8 @@ pbr
psutil
pyOpenSSL
python-keystoneclient
+# required by `oslo_cache` when imported by `keystonemiddleware`
+python-memcached>=1.56
python-barbicanclient
python-swiftclient>=3.2
git+https://github.com/cloudbase/pywinrm.git@requests#egg=pywinrm