Ability to defer issues
Description
I would love the ability to defer issues, because they are either blocked or you have to wait until some release before this issue becomes relevant. Deferred issues shouldn't pop up in the index view unless the user sets it as parameter in the search bar.
Inspired by: https://gitlab.com/gitlab-org/gitlab-ce/issues/30876#note_27381983
Proposal
We have a due date for issues, now I want something like it: a deferred date.
Links / references
Inspired by Omnifocus' deferred items.