MQTT Binding - where to download

In the GITHUB that the MQTT binding is available as a separate optional download, but no links to show where from…

Total beginner to OpenHab, just installed it this afternoon.
I have a few ESP8266 around the house that report temperature, report presence,control lights - all using MQTT.
I had been using just a simple MQTT client to control them.
I want to add these into OH along with a new selection of Energenie items.

OH is installed on an Intel Compute Stick with Win 10, along with Mosquito.

Any guidance on where to get MQTT bindings and the setup would be great.

Documentation is here.

Download of 1.7.1 bindings are here.

Thanks - missed the obvious - When the notes said a separate down load…