Changed description for Dancing Swords to work with any item. I didn't change...

Changed description for Dancing Swords to work with any item. I didn't change the name of the spell, since I don't know where else in the book is it referenced, but it could use a name change, for clarity's sake. Skill used for the spell is changed to 'Varies', so it would depend on an item. Performance for musical instruments, Larceny for lockpicks, Combat for weapons, etc.
Also, some numbers in the example were wrong, so I recalculated them, compare with the original. 
Also also, why would you use Potent Dancing Swords as an example for Dancing Swords? Changed that too.