add pictures to read me github code example

Example 1: github add image readme

# ![alt text](url)
![My image](http://url/to/image.jpg)

# You can now drag and drop the images while editing the readme file.
# Github will create a link for you which will be in the format of:
https://user-images.githubusercontent.com/******/********.file_format

Example 2: how to add image in readme.md

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