Apply explosion knockback to projectiles

[tesselslate]

Explosion knockback currently does not apply to projectiles. This PR makes projectiles (arrows, snowballs, etc) take knockback from exploding TNT (see upstream issue, fix).

Feel free to let me know if anything is wrong with this or needs adjusting. I've never done any server modding before and am not sure if this has any subtle adverse effects. I've also encountered an issue with the paperclip target (related?) but the normal build seems to work fine.

https://user-images.githubusercontent.com/46545045/167948979-51ee6c87-82c4-494e-844b-7ecc4c71897d.mp4