List lookup to actual math

"Replaced var/sizes_to_number with weirdass formula that is faster and takes up less space in code than list lookups"

Affected code are all from 5cfa0df3d29a2f631e16e7ee0cc24ab9ca3fe566
If anyone would like to change it so that smaller items get sucked *first*, change line to

`if(prob(current_size * 5) && hand.w_class <= ((current_size+1)/2)  && H.unEquip(hand))`