code: function RedisStore(opt){
    this._options = opt || {};
    this.redis = opt.client || RedisStore._createClient(opt);
    this.redis.debug_mode = /redis/i.test(process.env.DEBUG);
  }
docs: @class
  
  @private
  
  @description
  
  Caching implementation that uses Redis as data storage.  If an existing
  client instance is not provided, this constructor will create one. Utilizes
  the [node-redis](https://github.com/NodeRedis/node_redis) library.
  
  @param {Object} [options]
  @param {Object} [options.client] A redis client instance
  @param {Object} [options.connection] Redis client constructor connection options
  @param {Number} [options.connection.port] DB port number
  @param {String} [options.connection.host] DB host name
  @param {*} [options.*] Other options to pass to the Redis client constructor.