Mention Chess Match Viewer (PyScript) in README (#890)

* Mention Chess Match Viewer (PyScript) in README

Would it be okay to mention this PyScript demo here? Hope the formatting is suitable.

* Putting back accidentally removed blank line

Error indicates that a blank line is needed after the bullet list. I seem to have removed the line accidentally and the GitHub editor was more forgiving than the rst process

Author: nmstoker

README.rst

@@ -342,6 +342,7 @@ If you like, share interesting things you are using python-chess for, for exampl
 * an `Alexa skill to play blindfold chess <https://www.amazon.com/Laynr-blindfold-chess/dp/B0859QF8YL>`_ – https://github.com/laynr/blindfold-chess
 * a chessboard widget for PySide2 – https://github.com/H-a-y-k/hichesslib
 * Django Rest Framework API for multiplayer chess – https://github.com/WorkShoft/capablanca-api
+* a `browser based PGN viewer <https://about.nmstoker.com/chess2.html>`_ written in PyScript – https://github.com/nmstoker/ChessMatchViewer
 
 Acknowledgements
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