Dungeon additions & improvements

The Dungeons pack could use some more assets for common use cases such as:

• Gritty table without paper

• More crystal shales

• Individual tomes

• Cracks in the ground (similar to the Fantasy Regional ones)

• Cracks filled with lava

• Fallen over mine cart

• Fire

• Lava holes

• Sitting skeleton

• Small sone pebbles

• stalagmites & stalactites

• Wooden poles

• non-patched tents