Variable proximity distances

[ProgrammerDan]

From ShadedJon:

is it possible to make orefubscator work at different lengths?
So make it configurable to make diamondore show up if you're 3 blocks away
but coal ore if you're 7 blocks away

[Aleksey-Terzi]

Just to note.
I first need to refactor how configurations is managed.
Now it is static class with static fields with cross references between other classes, which is hard to make to work as hierarchy structure.
Then I want to make per-world support for configuration (should be not hard after refactoring)
After all of this - "Variable proximity distances" will be easy to do.