Extend decorators to make fields clickable in search results

This came up because I build a field from a snort rule id and concat it with the full ET website. I end up with a value like this http://doc.emergingthreats.net/2016502.

I understand this is not currently possible but would like to request consideration for extending the decorators functionality. ref: https://groups.google.com/forum/#!topic/graylog2/3628vZcwUB0

Regards,
Brandon