Nature Swap: Correctly fix EVs and IVs (#4452)
Nature Swap: Correctly fix EVs and IVs (#4452)

The previous method would cause the EVs and IVs in a stat to swap every
time a Pokemon switched out.
xfix/Pokemon-Showdown,panpawn/Gold-Server,panpawn/Pokemon-Showdown,jumbowhales/Pokemon-Showdown,AustinXII/Pokemon-Showdown,Zarel/Pokemon-Showdown,AustinXII/Pokemon-Showdown,sirDonovan/Pokemon-Showdown,svivian/Pokemon-Showdown,xfix/Pokemon-Showdown,jumbowhales/Pokemon-Showdown,Enigami/Pokemon-Showdown,Zarel/Pokemon-Showdown,urkerab/Pokemon-Showdown,svivian/Pokemon-Showdown,Zarel/Pokemon-Showdown,sirDonovan/Pokemon-Showdown,Enigami/Pokemon-Showdown,AustinXII/Pokemon-Showdown,QuiteQuiet/Pokemon-Showdown,QuiteQuiet/Pokemon-Showdown,panpawn/Gold-Server,xfix/Pokemon-Showdown,jumbowhales/Pokemon-Showdown,sirDonovan/Pokemon-Showdown,QuiteQuiet/Pokemon-Showdown,panpawn/Pokemon-Showdown,svivian/Pokemon-Showdown,xfix/Pokemon-Showdown,xfix/Pokemon-Showdown,Enigami/Pokemon-Showdown,urkerab/Pokemon-Showdown,svivian/Pokemon-Showdown,urkerab/Pokemon-Showdown,Enigami/Pokemon-Showdown,panpawn/Gold-Server,svivian/Pokemon-Showdown