Also accept timeout parameter in FakeMemCache

When fake.cache is set, current master keystoneclient
is setting timeout= parameter instead of time= parameter
in set due to https://bugs.launchpad.net/swift/+bug/1095730

Change-Id: Ied8ffd6ac9738951d48e74a496a8777928fcc0d9

tests/api/v2/acl.py

@@ -64,7 +64,7 @@ class FakeMemcache(object):
                     ]},
             }}, dt.strftime("%s"))
 
-    def set(self, key, value, time=None):
+    def set(self, key, value, **kwargs):
         self.set_value = value
         self.set_key = key