The javascript app in /public/js/bundle.js is ready to go as-is, but it must be delivered via a webserver.
To use the built-in webserver with TreeTangler, you need to install from https://nodejs.org;
it will autodetect your OS. To launch a webserver on localhost, do npm start and it will
give you the localhost web address that is running the app.
The command line tools are available independently at https://github.com/meekrob/cophy-treetools