Add some authtoken related attributes

This change adds some attributes into the cookbook so
that they are configurable. It mainly includes:
cafile, memcached_servers, memcache_security_strategy,
memcache_secret_key, insecure and hash_algorithms.

Change-Id: I97877cf5ce48bd70b9cb2ff12b1fdffbd5a7a69d
Closes-Bug: #1371438