add images to project README on GitHub

The usual markdown syntax applies, e.g.,

![alt text](path/to/file)

1. add a png image to your gitHub project repo, e.g., in an assets folder just below your root (alternatively , you can set up a separate repo just for images, etc.)

2. this image must be a versioned file in the git index (add/commit/push, and not excluded in your .gitignore)

3. once the image is in your repo, click on it from gitHub and then click raw, a button at the upper right of the edit window

4. copy the URL that appears in your browser bar

5. place that URL inside the parenthesis for the markdown image link syntax, ie, in your README replace path/to/file above with this URL

6. (obviously) stage, commit, & push those changes to your README.