code: function RedisCacheStore(options) {
      options = options || {};
      options.db = options.db || 0;
      CacheStore.call(this, options);
      this._setStoreType(STORE_TYPE_REDIS);
  }
docs: Constructor to create cache store in redis db.
  options:
  [expires]: {Number} Seconds after cache item expires. Default @AppProperties.DEFAULT_EXPIRATION_TIME
  [keyPrefix]: {String} Prefix before key of this cache. Default is current millis
  [db]: {String} Redis DB name
  @param [options]
  @constructor