mcMMO Simple Econ Rewards

This is updated to have support for rewarding on power levels, or each individual skill. For example, if you have a reward of $50 set at level 5, if rewarding for power is on, then it will reward that $50 when any players reach level 5 total level. If it's false, then they would receive it when they reach level 5 mining, woodcutting, archery, and so on.