Cooldown groups for weapons/capsules

[PFQNiet]

Currently, all weapons share a cooldown, and all capsules share a cooldown.

I have a powerful healing item that fully heals your character but has a several second long cooldown. During this cooldown, it's impossible to throw grenades because they are also capsules.

I would like to suggest a `cooldown_group` property, which will allow modders to have capsules of different types have different (potentially shared) cooldowns. In my case, I could have `cooldown_group = "healing"` for my healing items, and that would neatly solve my problem.

Weapons would be nice too - I have a gun with a fast shooting speed but slow reload speed. It would be nice if, during that reload, you could cycle to a different weapon to shoot that instead. Imagine the weapon is a Minigun, and the "reload" represents letting it cool off after firing a volley, you should be able to pull out a pistol in the meantime.