Improve types for Image Component (#17954)
Improve types for Image Component (#17954)

![Screenshot on VS Code](https://user-images.githubusercontent.com/12539/96300300-43fc1280-1030-11eb-89ae-dba8beeca583.png)

The only attribute that must be used with Image Component is src, but all attributes are required and TypeScript will warn you.
zeit/next.js,flybayer/next.js,JeromeFitz/next.js,JeromeFitz/next.js,flybayer/next.js,azukaru/next.js,flybayer/next.js,JeromeFitz/next.js,zeit/next.js,azukaru/next.js,azukaru/next.js,zeit/next.js,JeromeFitz/next.js,azukaru/next.js,flybayer/next.js