Allow negative values in Max Lvl Below Character Level filter rule

Use case: I want to hide all normal/magic/rare items with a requirement above my character’s level, or maybe more than 3 levels away from me being able to put it on. This would make levelling feel a bit smoother since I wouldn’t be seeing items I can’t put on (and may not be able to put on for a long time). Currently the best I can do is put a 0 in the box, but then I’m hiding stuff exactly equal to my level which isn’t my intent.