[PD-767] Used FSM widget for seo sites.

All hands on deck. I changed to using an FSM widget, but I'm not fluent enough with our admin to know what else would need to be looked at to determine if I broke other things. I also wouldn't begin  to know what kind of tests to run against this, since the offending behavior is provided in javascript and what we are testing is load speeds. I also suspect that there might be a lot of code duplication, but the lack of documentation and admin's notoriety make me hesitant to try and improve on the situation. 
We'll definitely want `fields = ('domain__icontains', )`. I'm not sure if there are any other fields they search on.