add link to Colab

README.md

@@ -52,6 +52,8 @@ results = corrector(raw_text)
 print(results)
 ```
 
+Check out a simple demo in [Google Colab here](https://colab.research.google.com/gist/pszemraj/06fac5b608889e258229a659cc53485f/demo-for-grammar-synthesis-small.ipynb).
+
 ## Model description
 
 The intent is to create a text2text language model that successfully completes "single-shot grammar correction" on a potentially grammatically incorrect text **that could have a lot of mistakes** with the important qualifier of **it does not semantically change text/information that IS grammatically correct.**