Sort artefact array in test before asserting it
Add integration tests for the new filters
Set up sass-rails for Panopticon
Show the number of matching artefacts in big type

This shows the number of artefacts which match the current search or 
filter.
Tweak styles for the artefacts layout

- Remove the "Artefacts" header from the page (the number of artefacts 
is a better indicator of what the user is viewing).
- Restore the original width of the filters column (span2).
- A few padding and margin tweaks to the filter form.
Fix the selected value of filter box when blank

When there's no filter applied, the select box should explicitly mark 
the "All" option as "selected".