models: `Clns::CacheBook` and embedded model, skeleton
i18n: `cache_book.yml` initial translation
views: `Clns::CacheBook` CRUD skeleton, for testing
views: `pdf.rb` Prawn skeleton, template
assets: css, base completions
js, `Clns.desk.scrollHeader` reset functionality
assets: js, `Clns.desk.cache_book` skeleton
update CHANGELOG
bump version v0.2.12
Merge branch 'feature/v0.2.12' into develop