Similarity check (iThenticate/crosscheck) warning on non-checked manuscript files

[severett89]

At the moment it is pretty easy for editors to miss requesting a similarity check on manuscripts that have been submitted to a journal in the 'unassigned' atage. It would be good, if crosscheck/similarity checking is enabled for that journal, for an editor to be made aware that a similarity check has not been performed on an article's files prior to an action being taken on the article, for example, moving it to formal peer review, declining it, etc. This could be via a popup in Janeway when an action is clicked in the actions pane, perhaps?