i18n-tasks (rubygems): i18n-tasks helps you find and manage missing and unused translations.  It analyses code statically for key usages, such as `I18n.t('some.key')`, in order to report keys that are missing or unused, pre-fill missing keys (optionally from Google Translate), and remove unused keys. 
Keywords: i18n|ruby|static-analysis|static-code-analysis|translation-management