Adds /money.

This is a fork of money2 that uses more modern APIs such as mod storage and is fully backwards compatible with money2 (you can upgrade from money2 nicely, however you can't downgrade again).

Config settings

These can be set in config.lua or minetest.conf.

    gold = { item = "default:gold_ingot", dig_block="default:stone_with_gold",
        desc='Gold', amount=75, minval=25 },
    silver = { item = "moreores:silver_ingot",
        dig_block="moreores:mineral_silver", desc='Silver', amount = 27,