use image in readme code example

Example 1: add image to readme

![alt text](http://url/to/img.png)

Example 2: how to add image in readme

Try this markdown:

![alt text](http://url/to/img.png)
I think you can link directly to the raw version of an image if it's stored in your repository. i.e.

![alt text](https://github.com/[username]/[reponame]/blob/[branch]/image.jpg?raw=true)