6.4.0

Feature

• Translated workflow state in contents @nzambello
• Added item type as a tooltip in contents @nzambello
• Added italian translations and translated array, token and select widget. @giuliaghisini
• Added uploading image preview in FileWidget @iFlameing
• Allow custom express middleware declared with settings.expressMiddleware. See Customizing Express @tiberiuichim

Bugfix

• Fix the toolbar dropdown to add content types if isMultilingual is enabled
  but a type is not marked as translatable. @csenger
• Usage of Contettype label in Add component. @giuliaghisini

Internal

• Update upgrade-guide to for addonRoutes and addonReducers @jackahl