Inheritance fixes
Inheritance fixes

- Allow inheritance from banned Pokémon.
- Prevent megas/primals from starting battles not in base forme.
- Improve error messages. In particular, banned Pokémon are now
explicitly marked as such, rather than mixed with general
illegal sets.

ZestOfLife/FestiveLife,Alpha-Devs/Alpha-Server,Firestatics/omega,Pikachuun/Pokemon-Showdown-SMCMDM,ShowdownHelper/Saffron,jd4564/Pokemon-Showdown,ehk12/coregit,Alpha-Devs/OmegaRuby-Server,CharizardtheFireMage/Showdown-Boilerplate,CreaturePhil/Showdown-Boilerplate,bai2/Dropp,ehk12/coregit,Hidden-Mia/Roleplay-PS,yashagl/yash-showdown,xfix/Pokemon-Showdown,AWailOfATail/Pokemon-Showdown,Zarel/Pokemon-Showdown,arkanox/MistShowdown,SolarisFox/Pokemon-Showdown,BlazingAura/Showdown-Boilerplate,Syurra/Pokemon-Showdown,Bryan-0/Pokemon-Showdown,panpawn/Gold-Server,aakashrajput/Pokemon-Showdown,TheManwithskills/COC,kuroscafe/Paradox,AbsolitoSweep/Absol-server,TheFenderStory/Pokemon-Showdown,AWailOfATail/awoat,yashagl/yash-showdown,KewlStatics/Shit,arkanox/MistShowdown,urkerab/Pokemon-Showdown,urkerab/Pokemon-Showdown,Git-Worm/City-PS,Firestatics/Omega-Alpha,svivian/Pokemon-Showdown,BlazingAura/Showdown-Boilerplate,PS-Spectral/Spectral,KewlStatics/Pokeindia-Codes,kotarou3/Krister-Pokemon-Showdown,ShowdownHelper/Saffron,xfix/Pokemon-Showdown,KewlStatics/Shit,Irraquated/Pokemon-Showdown,Sora-League/Sora,KewlStatics/Showdown-Template,Volcos/SpacialGaze,Lord-Haji/SpacialGaze,danpantry/Pokemon-Showdown,Enigami/Pokemon-Showdown,aakashrajput/Pokemon-Showdown,Wando94/Spite,Volcos/SpacialGaze,TheFenderStory/Showdown-Boilerplate,zek7rom/SpacialGaze,HoeenCoder/SpacialGaze,kuroscafe/Showdown-Boilerplate,ZestOfLife/PSserver,Ecuacion/Pokemon-Showdown,AnaRitaTorres/Pokemon-Showdown,psnsVGC/Wish-Server,panpawn/Gold-Server,Sora-League/Sora,QuiteQuiet/Pokemon-Showdown,AbsolitoSweep/Absol-server,svivian/Pokemon-Showdown,urkerab/Pokemon-Showdown,Sora-League/Sora,psnsVGC/Wish-Server,Nineage/Origin,AnaRitaTorres/Pokemon-Showdown,bai2/Dropp,SolarisFox/Pokemon-Showdown,sirDonovan/Pokemon-Showdown,Mystifi/Exiled,xfix/Pokemon-Showdown,AustinXII/Pokemon-Showdown,jd4564/Pokemon-Showdown,xCrystal/Pokemon-Showdown,Flareninja/Showdown-Boilerplate,DesoGit/Tsunami_PS,xCrystal/Pokemon-Showdown,Guernouille/Pokemon-Showdown,svivian/Pokemon-Showdown,Lord-Haji/SpacialGaze,AWailOfATail/Pokemon-Showdown,Wando94/Pokemon-Showdown,panpawn/Gold-Server,Kokonoe-san/Glacia-PS,kuroscafe/Showdown-Boilerplate,Mystifi/Exiled,yashagl/pokemon-showdown,AWailOfATail/Pokemon-Showdown,Ecuacion/Pokemon-Showdown,Pikachuun/Pokemon-Showdown-SMCMDM,Zarel/Pokemon-Showdown,TheManwithskills/Creature-phil-boiler,xCrystal/Pokemon-Showdown,TheManwithskills/Creature-phil-boiler,Lauc1an/Perulink-Showdown,HoeenCoder/SpacialGaze,danpantry/Pokemon-Showdown,aakashrajput/Pokemon-Showdown,kuroscafe/Paradox,TheManwithskills/DS,yashagl/pokemon-showdown,DesoGit/TsunamiPS,jumbowhales/Pokemon-Showdown,KewlStatics/Pokeindia-Codes,Hidden-Mia/Roleplay-PS,Nineage/Origin,Git-Worm/City-PS,Pikachuun/Pokemon-Showdown,Wando94/Spite,sirDonovan/Pokemon-Showdown,CreaturePhil/Showdown-Boilerplate,azum4roll/Pokemon-Showdown,TheManwithskills/COC,ZeroParadox/BlastBurners,xfix/Pokemon-Showdown,AustinXII/Pokemon-Showdown,panpawn/Pokemon-Showdown,Guernouille/Pokemon-Showdown,Lauc1an/Perulink-Showdown,Zarel/Pokemon-Showdown,HoeenCoder/SpacialGaze,Lord-Haji/SpacialGaze,TheFenderStory/Showdown-Boilerplate,KewlStatics/Alliance,cadaeic/Pokemon-Showdown,zek7rom/SpacialGaze,jumbowhales/Pokemon-Showdown,Irraquated/Pokemon-Showdown,Vacate/Pokemon-Showdown,AWailOfATail/awoat,kotarou3/Krister-Pokemon-Showdown,Mystifi/Exiled,Enigami/Pokemon-Showdown,DesoGit/Tsunami_PS,DarkSuicune/Pokemon-Showdown,Firestatics/omega,TheManwithskills/DS,Enigami/Pokemon-Showdown,KewlStatics/Alliance,Alpha-Devs/Alpha-Server,SSJGVegito007/Vegito-s-Server,Wando94/Pokemon-Showdown,QuiteQuiet/Pokemon-Showdown,DesoGit/Tsunami_PS,Alpha-Devs/OmegaRuby-Server,TbirdClanWish/Pokemon-Showdown,CharizardtheFireMage/Showdown-Boilerplate,ZeroParadox/BlastBurners,Syurra/Pokemon-Showdown,DarkSuicune/Pokemon-Showdown,AustinXII/Pokemon-Showdown,DesoGit/TsunamiPS,sirDonovan/Pokemon-Showdown,SkyeTheFemaleSylveon/Pokemon-Showdown,jumbowhales/Pokemon-Showdown,CreaturePhil/Showdown-Boilerplate,Irraquated/Pokemon-Showdown,Firestatics/Omega-Alpha,Enigami/Pokemon-Showdown,QuiteQuiet/Pokemon-Showdown,ShowdownHelper/Saffron,ZestOfLife/FestiveLife,PS-Spectral/Spectral,PS-Spectral/Spectral,TheFenderStory/Pokemon-Showdown,SSJGVegito007/Vegito-s-Server,SkyeTheFemaleSylveon/Pokemon-Showdown,EienSeiryuu/Pokemon-Showdown,Vacate/Pokemon-Showdown,KewlStatics/Showdown-Template,HoeenCoder/SpacialGaze,ZestOfLife/PSserver,Elveman/RPCShowdownServer,svivian/Pokemon-Showdown,cadaeic/Pokemon-Showdown,panpawn/Pokemon-Showdown,svivian/Pokemon-Showdown,Pikachuun/Pokemon-Showdown,TbirdClanWish/Pokemon-Showdown,Flareninja/Showdown-Boilerplate,Kokonoe-san/Glacia-PS,xfix/Pokemon-Showdown,Elveman/RPCShowdownServer,EienSeiryuu/Pokemon-Showdown,Bryan-0/Pokemon-Showdown,azum4roll/Pokemon-Showdown