### Option: use [Redis](http://redis.io) to store your access_token (Recommend)
**If you don't use Redis, it will send a request to get a new access_token everytime!**
* Added `redis-namespace` to you `Gemfile`
```ruby
# Adds a Redis::Namespace class which can be used to namespace calls to Redis. This is useful when using a single instance of Redis with multiple, different applications.