add img on readme github code example

Example 1: adding a preview image in readme.md

// method 1


// method 2
![Test Image 3](/3DTest.png)
![Test Image 4](https://github.com/tograh/testrepository/3DTest.png 112)

// last method

Example 2: README.md image

If you want to embed images, this is how you do it:

![Image of Yaktocat](https://octodex.github.com/images/yaktocat.png)