CTRL + ALT + A: Kill GTA
I included the .ahk script, but you don't need to use that unless you want to make changes or something.
If you just want to use it, double-click the .exe and you're set! No need to install AutoHotKey.
(if you don't like using the exe for safety purposes, you should install AutoHotkey and use the .ahk script instead)
-Gyfen