tsvector/tsquery-based full text search producing odd results

[toolness]

This has already been fixed in 5573b4a but I wanted to record the rationale behind it here.

Basically, the tsvector/tsquery-based full text search wasn't returning accurate results. If there were two users named Andrew in the system, it would only return one of them; searches for "govlab" only returned 4 people, while many more had "The GovLab" as their organization. Really weird stuff.

The fix uses ILIKE instead, which is almost certainly way less efficient, but will do for now, since we don't have a ton of users.