Fix Double and Float equality/hashCode in data classes

 #KT-5818 Fixed
Generate lambdas in enum entry super calls

 #KT-4423 Fixed
Prohibit to override equals/hashCode in enums

 #KT-5721 Fixed
Add toString() to kotlin.Enum

Overridable because it is in java.lang.Enum
Make enum classes comparable

 #KT-3727 Fixed
Regenerate test data on enums

Now they have final equals, hashCode and compareTo
(TODO FIX PARSER) Prohibit all modifiers for enum entries

 #KT-2679 Fixed
Minor, fix some warnings in DeclarationsChecker
Make 'when' on nullable enums exhaustive if 'null' entry is present

 #KT-2902 Fixed
Fix incorrect "senseless null in when" on nullable type
Prohibit type parameters for enum classes

 #KT-5696 Fixed