Rebalance various monster levels
All the discussions regarding monster distributions on levels and quest monsters given by Thrundarr let me to believe that I should adjust a couple of monster rarities: On later levels there are lots of very rare monsters but few uncommon or common monsters. Now most levels (that introduce new monsters) sport one monster type that is at least uncommon.
Quest monsters now are pretty decent across all levels and no particular monster type should be totally dominating on later levels.