v5.1.5 Prevent db race conditions while creating thumbs v5.1.4 Include necessary files in gem package v5.1.3 Use Alchemy 5.1.0.alpha v5.1.2 Add support for file attachments stored on S3 v5.1.1 Ensure to create new thumbs on in memory picture v5.1.0 Alchemy 5.1 support