You'll two key components, and one optional.
You'll need to download the Java 8 JDK from Orcale's website. (You need the JDK, the JRE is not enough).
http://www.oracle.com/technetwork/java/javase/overview/java8-2100321.html
The project is Mavenized, so you'll need the Maven build plugin.
Run the following command at the command line - mvn install
.
The project should now be ready to work with.