Adding Backpack Mod support

[Combatplaya]

I personally think that the backpacks mod should be supported on the server. I am a person who always has to go back and forth from a project to my house just to get supplies. With the backpacks mod, it would give a player more space for materials if they were building, mining, or even hunting. Thanks, Combatplaya.

[RedArrow]

I think we shouldn't add new things to the server. Nice idea though.