Redisson L2 cache

Hey!
I've created a [plugin](https://github.com/dragkes/ebean-redisson/tree/master) that provides L2 caching support using Redis, similar to  [ebean-redis](https://github.com/ebean-orm/ebean/tree/master/ebean-redis), but built with Redisson instead of Jedis.
Would appreciate it if you could take a look.