Impossible Mobs

Changelog: -Added command /impossiblemobs -Added /impossiblemobs enable Enables the plugin -Added /impossiblemobs disable Disables the plugin -Added /impossiblemobs limitworlds <true/false> Plugin will only be enabled in enable worlds if true -Added /impossiblemobs enableworld <world name> Adds a world to the list of enabled worlds (only works if limitworlds is true) -Added /impossiblemobs disableworld <world name> Removes a world from the list of enabled worlds (only works if limitworlds is true)