Introduce AWS S3.

Simple Storage Service, or S3 in short, is a storage option offered by Amazon for the internet. Storage for the internet means to store and retrieve any amount of data at any time from anywhere on the web. So any user with sufficient permissions should be able to upload new objects to this storage from anywhere on the globe. Also, clients with sufficient permissions should be able to download any objects from this storage using a simple internet connection. S3 is intentionally built with a minimal feature set that focuses on simplicity and robustness. It is easy to define public and private access roles which gives the flexibility to give read or write access permissions to target users. AWS S3 is highly scalable, reliable, fast, inexpensive data storage.