Enhancement: Allow Key Combos when configuring Controls

## What is your suggestion, and why should it be implemented?

When rebinding controls, we should have special modifiers keys (CTRL/COMMAND + ALT/OPTION), those special modifiers would wait for the next non-modifier key input, which would allow people to easily make key combinations.

e.g: Reload Scripts could be Shift+F5 by default, but in the controls menu, you can rebind it to Ctrl+Alt+F3