Update on close

[benwa]

I'd like an option for the user to install an update on the close of the application. When an update is available, the same popup will appear but with the ability to "schedule" the update so once the user is done with the application, it will begin installing. Paint.NET has this feature and I've found it a nicer UX flow that doesn't get in the way of the user working.

[vslavik]

Sounds useful. If you'd like it, please work on it and submit a PR.