Add MM changes to Player Beastiary and update Minor Illusion

[Danberms]

Per PHB errata, player bestiary stats should be based off of their MM entries if there is any discrepancy. With the MM Errata changing a couple of the beasts, I made the changes to reflect them in the players bestiary. They were the Elephant, WarHorse, Riding Horse, and Giant Rat Diseased. Corrected the average damage for the giant rat diseased in the MM per the errata. For Minor Illusion, the spell was missing the actual material used in the spell.

[Danberms]

Found a way to get this to work, hope this is how it should be done and how you like it.