V4.5.3 little fix

Hello, V4.5.3 had a little problem with the new interruption feature, it's fixed now. Unfortunatly, the new API function was removed but I made another thing instead : "instant_shooting()" which allows you to bypass the cooldown of a list of bullets and shoot them right away. I also went back on the decision to make customFunction.gd downloadable separatly. This new version has only the BuHSpawner.gd and TriggerContainer.gd changed so you can only replace those ones in your project.