HV-924 Enabling Animal Sniffer per default in the relevant HV modules and marking classes targeting Java 8
explcitly via an annotation to be ignored by AnimalSniffer
HV-925 Javadoc cleanup
HV-925 work in progress ...

- Adding a boolean flag to @UnwrapValidatedValue to allow to explicitly specify unwrapping or skipping of unwrapping
- Introducing ValidatingValueUnwrapMode used by metadata to distinguish between the different potential ways of handling unwrapping of validated values
- Updating all levels of metadata and metadata builders to make use of ValidatingValueUnwrapMode
- Updating test, splitting some of them into smaller ones
HV-925 Javadocs
HV-925 Fixing isConstrained()
HV-925 Updating tests
HV-925 Formatting
HV-925 tests passing