No maven repo is available at the moment. So, you need to download the binaries and put them into your WEB-INF/lib folder. No extra dependencies than a JSF implementation is required. All you have to do is putting html5-comp-lib-core-0.x.x-SNAPSHOT.jar and myfaces-shared-html5-0.x.x-SNAPSHOT.jar into your WEB-INF/lib, just like any other web project artifact.
You can download the binaries from here. But these binaries may not be up-to-date.
You can download the sample application WAR from here. Dependencies are already included in the WAR file, so this might be a good starting point.