Game mode integration

[CarsonBurke]

Is your feature request related to a problem? Please describe. Nope

Describe the solution you'd like A checkbox to toggle the running of gamemode (via gamemoderun or gamemoded -r [PID]) for each game.

Describe alternatives you've considered Probably not many alternatives

Additional context Lutris has a version of this with Feral Game Mode, which toggles gamemode

In steam this is done with gamemoderun %command%

Thank you Kramo for your wonderful work on this project