Added Apache's "geoip" module to puppet's dependencies. Refs #115

For testing on Travis we may use:

  - sudo touch /var/www/ads/index.php
  - sudo chown travis /var/www/ads/index.php
  - echo "<?php print_r(geoip_record_by_name('php.net')); ?>" > /var/www/ads/index.php
  - sudo wget -qO- http://ads.server/ | cat