Make result count show for keyword only searches

Add keyword presence into the boolean any_filters_applied?
Merge pull request #68 from alphagov/fix-no-results-keyword-buglet

Make result count show for keyword only searches
Make keywords show up in search results

Before, the search summary didn't show up keywords. This commit adds keywords to the summary and adds tests.
Add Airbrake
Merge pull request #71 from alphagov/airbrake

Add Airbrake
Reword tests
Merge pull request #70 from alphagov/add-sentence

Make keywords show up in search results
Use Rummager as search backend

Replacing soon to be decommissioned Finder API which is still in use for
sharing schemas.