Update readme with configuration section.
Update readme with configuration section.

wallymathieu/NHibernate.Caches.StackExchange.Redis,TheCloudlessSky/NHibernate.Caches.Redis,EzyWebwerkstaden/NHibernate.Caches.Redis,wallymathieu/NHibernate.Caches.StackExchange.Redis,wallymathieu/NHibernate.Caches.StackExchange.Redis