Added Redis Brain implementation

Adds support for a Redis brain. To implement redis on windows:

* cinst redis-64
* Install the [redisService.exe windows service mplementation](https://github.com/kcherenkov/redis-windows-service) into the chocolatey folder and register as a service
* make sure you have the mmbot.redisbrain.dll in your mmbot folder and...
* add the following config

```
[BRAIN]
NAME = REDIS
```