Add docs for publishing the playground

README.md

@@ -111,5 +111,17 @@ npm test
 npm run coverage
 ```
 
+## Publishing to GitHub Pages
+```bash
+npm run deploy
+```
+
+This will push the currently built playground to the gh-pages branch of the
+currently tracked remote.  If you would like to change where to push to, add
+a repo url argument:
+```bash
+npm run deploy -- -r <your repo url>
+```
+
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