Configuration/setting overall ore scarcity

[rasusmilch]

I changed a few setting under the ore spawning cluster sizes, as grinding away in the mines for hours got boring when I have limited time to play.

It would be nice to have some kind of configuration to adjust the amount of ore/diamonds/etc that are generated in a world. Perhaps some kind of overall multiplier? I made a simple change to up all ore cluster sizes to 10 which I then can grind out some and play more of the game than watching my pickax for 4 hours. One finds diamonds rarely, but you get a larger haul of them (and all ore) which allows me to get out of the work and go play. :)

I'm sure this isn't how MineCraft does it, but would be a nice-to-have.