Fix puppet-apply test for Debian Jessie

The version of puppet 3.x in Debian Jessie is 3.7.2, which seems to be
unable to read the modulepath setting from environment.conf. Since we
only have the one environment, the quick fix is to link the module into
the standard module path.

Change-Id: I6f4fa87fa4941c29abf37c277f5ce895a51945bc

tools/prep-apply.sh

@@ -77,6 +77,8 @@ sudo mv /tmp/hosts /etc/hosts
 # of configuring hiera.
 sudo mkdir -p /opt/system-config
 sudo ln -sf $(pwd) /opt/system-config/production
+# Really make sure that the openstack_project module is in the module path
+sudo ln -sf /opt/system-config/production/modules/openstack_project /etc/puppet/modules
 sudo -H mkdir -p ~/.ansible/tmp
 
 virtualenv --system-site-packages /tmp/apply-ansible-env