• Upgrade to Kotlin 1.9, requiring Kotlin 1.7+ to use this library
• Make ValidationResult covariant (#56 by @nlochschmidt , #94 by @dhoepelman )
• Add ifPresent and required validations for nullable types (#56 by @nlochschmidt )
• Deprecate ValidationErrors in favor of List<ValidationError> (#95 by @dhoepelman )
• Add uuid() validation for Strings (#49 by @vitorfec)