High: Upgrade redis to the version of 3.1.1 or higher to fix vulnerability issue

[Marek Dano]

We use this lib on the production and there is a reported vulnerability issue in the Redis version that you currently use 3.0.2.

Can you please upgrade the redis to version 3.1.1 or higher?

[Marc Harter]

Thank you! Published in 5.2.0