Allow arbitrary values for suspend timeout

[Anjune M]

Just a wish: In the power settings, i'd be really nice to be able to simply enter a value for the suspend (sleep) timeout directly. A slider that seems to top out at one hour (though it's not clear what happens between that mark and "never") doesn't account for use cases where you know you'll need the computer running for the length of a movie, three podcats, some number-crunching or backup duties or anything else you might not be awake, there, or willing to wait for to end. Same with any similar timeouts, of course. I suppose gsettings or dconf-editor can work around that, but that's hardly discoverable :)