v0.5.0

• acts_as_reader: Added optional :scopes option
• .mark_array_as_read: Better performance
• Rails 4.2 compatibility (thanks to @JuanitoFatas)
• Improved error messages (thanks to @kyuden)
• Migration: Removed harmful string length limit
• Use rails standard way reference to declare polymorphic associations (thanks to @wangqiang1208)