Handler unloading

[inglettronald]

Description

Allows the user to close/unload ClientBoundPacketHandler implementations.

Why?

Dynamic handler loading seems like a novel idea.

[ConnorLinfoot]

I don't necessarily disagree with adding an option to remove handlers, but why would we need a close method? If you have the reference to the handler instance you should be able to handle anything else as a result of removing the handler yourself.

[inglettronald]

The user could certainly call there own close method after removing a handler. However, it looks like all of the mods can access each-other handlers currently, and this close method followed that expectation.

[ConnorLinfoot]

The handlers registered aren't currently accessible, the only way to add a handler is to provide the handler itself. Other mods don't have access to the handler added.

[inglettronald]

Other mods should be able to access it through mixin, reflection, or access wideners. However, at that point you could probably write your own injection into unregisterHandler anyway to write a close method, so I don't really care if this close method gets kept or not.

[ConnorLinfoot]

I think with the current goals and implementation of the Mod API, methods to unregister handlers are unnecessary