Add Inverse Tiers && Previous Gens Randbats (#171)
Add Inverse Tiers && Previous Gens Randbats (#171)

- Inverse Added: Could honestly add more it's just a little function to add.
- Past Gens: Why doesnt main have Gen 3/4 Randbats? 
- Plans: Perhaps work on a tier that makes Super Effectives Immunities?
panpawn/Pokemon-Showdown,Git-Worm/City-PS,panpawn/Pokemon-Showdown,panpawn/Gold-Server,panpawn/Gold-Server,Git-Worm/City-PS,panpawn/Gold-Server