Bobby

Seems that **Duration** class has been added since Java SE 8: [Official Doc](https://docs.oracle.com/javase/8/docs/api/java/time/Duration.html) I think the project cannot depend on Java 8 because it obviously states the support of Java...

My pull request to fix this issue was accepted. Please check which version you're using.

Here's the commit in which pull request #113 was merged: https://github.com/debop/hibernate-redis/commit/6914b154f9989d06e4421c530ce505ca74a110c6