'Add installation instructions for node_exporter
Add these to the start of the script so we can monitor installation.'

def __inject_prometheus_node_exporter(self, options, script):

    version = '0.14.0'
    node_version = 'node_exporter-{0}.linux-amd64'.format(version)
    install_node_exporter = ['curl    -s    -S    -L    -o    /tmp/node_exporter.gz    https://github.com/prometheus/node_exporter/releases/download/v{version}/{node_version}.tar.gz'.format(version=version, node_version=node_version), 'sudo    tar    xzf    /tmp/node_exporter.gz    -C    /opt', 'sudo    ln    -fs    /opt/{node_version}/node_exporter    /usr/bin/node_exporter'.format(node_version=node_version), 'rm    /tmp/node_exporter.gz', 'echo    "start    on    filesystem    or    runlevel    [2345]"    |    sudo    tee    /etc/init/node_exporter.conf', 'echo    "exec    /usr/bin/node_exporter    2>&1    /var/log/node_exporter.log"    |    sudo    tee    -a    /etc/init/node_exporter.conf', 'sudo    chmod    644    /etc/init/node_exporter.conf', 'sudo    service    node_exporter    restart']
    script.reverse()
    install_node_exporter.reverse()
    script.extend(install_node_exporter)
    script.reverse()
