Add invalidation reason to dataset

[Palollo]

When the user invalidates a dataset the UI should show a field to let the user specify the reason.
It is recommended to show some predefined reasons like: "It is a discarded/useless draft", "It contains some rejected subject or study", "It contains corrupted data", "Other".
And if "Other" is selected, let the user write the reason.
Then the property invalidationReason in dataset should be set with a PATCH operation.

When the dataset is invalidated a warning message is currently shown:

So now the content of property invalidationReason should be included in that warning message.