Translate action keys in Workflow analytics

The Workflow analytics shows the action keys, which may be difficult to decypher for a non technical user.

See

Therefore it would be nice to use i18n to translate these values in the element nuxeo-workflow-analytics.

At the same time, it would be nice to add the translations for the transitions used in the default Nuxeo workflows : see https://connect.nuxeo.com/nuxeo/site/studio/ide?project=NuxeoDMDefaultConfiguration_nux#@feature:SerialDocumentReview.workflow;4