add example image

Author: edwardchalstrey1

.gitignore

@@ -137,7 +137,9 @@ cython_debug/
 # Project specific
 *.tex
 *.pdf
+# Ignore PNGs by default, but allow PNGs in the repository `img/` directory
 *.png
+!/img/*.png
 *.aux
 *.log
 *.fls

README.md

@@ -9,6 +9,8 @@ Game tree drawing tool for publication-ready extensive form Game Theory games. G
 
 > `draw_tree` was originally developed by [Bernhard von Stengel](https://www.lse.ac.uk/people/bernhard-von-stengel) at the London School of Economics. It is being developed further as part of the [Gambit project](https://www.gambit-project.org) out of The Alan Turing Institute.
 
+<img src="img/one_card_poker.png" alt="Poker example" />
+
 ## Table of Contents
 
 - [Installation](#installation)