Rename `nginx` to `ll-nginx` in recipe comments
Add attribute to disable geoip module by default

GeoIP recipe (`recipes/http_geoip_module.rb`) downloads packages from
maxmind.com. In order to comply with AWS Security Best Practices,
require the attribute `node['nginx']['geoip']['enable']` to be set
to `true` before letting `remote_file` resource fetch packages from
maxmind.com.
Update `CHANGELOG.md` and tag v0.1.1 release