We do not skip all responses containing a Vary in the cachign mechanism
anymore. Under certain conditions such responses might be cached.
The cache won't store and won't deliver objects in these cases:
- If the response is not a 200
-- If the response contains a Vary header
+- If the response contains a Vary header and either the process-vary option is
+ disabled, or a currently unmanaged header is specified in the Vary value (only
+ accept-encoding and referer are managed for now)
- If the Content-Length + the headers size is greater than "max-object-size"
- If the response is not cacheable
- If the response does not have an explicit expiration time (s-maxage or max-age