Add support for "Show/Hide outdated"

Signed-off-by: Jonas Franz <info@jonasfranz.software>

options/locale/locale_en-US.ini

@@ -764,6 +764,8 @@ issues.review.comment = "reviewed %s"
 issues.review.reject = "rejected these changes %s"
 issues.review.pending = Pending
 issues.review.review = Review
+issues.review.show_outdated = Show outdated
+issues.review.hide_outdated = Hide outdated
 
 pulls.desc = Enable merge requests and code reviews.
 pulls.new = New Pull Request