* Clean up redis configuration
- put redis configs into their own struct
- put a redisConf struct into the default config so that envstruct
will populate it
- allow tweaking of retry, db index and read/write timeout settings
- update example config.yaml
This is potentially a breaking change for anyone who's been using
the redis backend already, but maybe that's just me? :)
* fix struct tags and s/Db/DB/
* remove unnecessary declarations
- add a redis store implementing stores.Storage
- add config file support to pick a storage backend
- add config file support to set redis host:port and password
- add docker_releases to .gitignore
- update README to mention redis support
- update example config.yaml
memory