Revert "WICKET-5350 remove wildcards from #ofList() and others"

This reverts commit ee41e39a5695bef0f6fc3c31b38e5f78de21d018.

Revert to make Wildcard**Model classes deprecated.
WICKET-5350 remove wildcards from #ofList() and others

Reapply ee41e39a5695bef0f6fc3c31b38e5f78de21d018 by just making Wildcard**Model classes deprecated, instead of completely removing them.
WICKET-5350 Use Model.ofList()

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