DATAREDIS-188 - Infinite loop renaming a non-existent Collection when using Lettuce.

We run into an infinite loop in org.springframework.data.redis.support.collections.CollectionUtils.rename(K, K, RedisOperations<K, ?>) if no value was associated with the key which leads to operations.hasKey(...) always returning false which prevents the actual renaming. RedisCollections will only send rename command if values are present as empty collections cannot be stored and therefor cannot be renamed.

Original pull request: #28