Use bluebird as the global Promise implementation
Return a 404 for getLatestFormat of a missing page
Merge pull request #74 from wikimedia/no-latest-rev

Return a 404 for getLatestFormat of a missing page
Merge pull request #75 from gwicke/bluebird

Use bluebird as the global Promise implementation
Fix the fails() by repurposing it as an assertion
Merge branch 'fails-fails' into spec-tests