GravityWorld

I have tried a new way to do it, so it seems that it can finally be released for 1.19.2.
at the moment it has problems with the projectiles, (only that they fall over and over again is not a serious clich, even so it is not yet very tested and I will accept comments about errors :))
 and I plan to make an adjustment so that the projectiles do not throw any block (added because at great depths practically nothing falls to avoid large knockdowns if it is not so bland :))