Tinder is not an end product in itself. It’s a library that can be used to build XMPP related functionality (Openfire itself, for example, uses Tinder and includes a copy).
I’m not sure what you are trying to do: do you want to run Openfire? If so, there’s no need for you to “install” Tinder. Are you trying to create a plugin for Openfire? Ifso, you can make use of the Tinder API without including Tinder explicitly (as it is included in Openfire). If you want to develop a stand-alone application that uses Tinder, the easiest way to include it is to add Tinder as a Maven artifact in your new project. Adding the Tinder library jar in your classpath will work too, of course.