feat: ability to inverse weights of WalkerTableBuilder

[DanArmor]

Maybe it can be useful for others
My use case, that lead to this:
I have an array of distances (for example [10, 30, 40, 50, 80]) and i want to pick more frequently shorter paths. So I just use implemented inverse() for table and get table as if the given distances were [80, 50, 40, 30, 10]
some more examples:
[1, 1, 10] inverse() [10, 10, 1] inverse() [1, 1, 10]
[5, 2, 6, 9] inverse() [4, 9, 3, 2] inverse() [5, 2, 6, 9]

[DanArmor]

@ichi-h mentioning just in case