The demo instance of planningpress. Essentially, this repo contains WordPress 3.4.1 (which can be downloaded from https://wordpress.org/download/release-archive/). None of these files should be modified, except wp-config-sample.php per "Editing wp-config.php".
The planningpress-demo should be installed per usual. After installation, the planningpress-plugins repo should be added to the wp-content/plugins directory and the planningpress repo should be added to the wp-content/themes/planningpress directory.