Update debug information on search results

For people such as search analyists who need to be able to see positions
and slugs for links (without hovering) to let them do their job more
efficiently.

![screenshot](http://f.cl.ly/items/0o243I3Y0X1e3D453Y0l/Screen%20Shot%202014-06-19%20at%2011.08.01.png)
The score is not a proportion; it's an arbitrary number.  Just returning the raw score is most useful.