The only necessary change is the one line in extension.js. I removed the proceeding slash and .js on the require.js import. Without the slash, you trust that Jupyter's require.js configuration knows where to find the extension.
I also added a postBuild file and MyBinder button for easily testing and demoing the extension. If you don't want those, let me know and I will remove them from the pull request.
The only necessary change is the one line in extension.js. I removed the proceeding slash and .js on the require.js import. Without the slash, you trust that Jupyter's require.js configuration knows where to find the extension.
I also added a postBuild file and MyBinder button for easily testing and demoing the extension. If you don't want those, let me know and I will remove them from the pull request.