added EvalfMixin to FiniteSet and Union
added EvalfMixin to FiniteSet and Union

This used to be handled by RealSet and the Real(FiniteSet/Union) classes

dqnykamp/sympy,iamutkarshtiwari/sympy,beni55/sympy,aktech/sympy,Titan-C/sympy,moble/sympy,AunShiLord/sympy,Designist/sympy,abhiii5459/sympy,grevutiu-gabriel/sympy,shipci/sympy,AunShiLord/sympy,abloomston/sympy,hargup/sympy,amitjamadagni/sympy,sunny94/temp,jaimahajan1997/sympy,skidzo/sympy,yukoba/sympy,grevutiu-gabriel/sympy,MechCoder/sympy,beni55/sympy,dqnykamp/sympy,shikil/sympy,cswiercz/sympy,amitjamadagni/sympy,MridulS/sympy,aktech/sympy,sampadsaha5/sympy,skidzo/sympy,lidavidm/sympy,kmacinnis/sympy,postvakje/sympy,pandeyadarsh/sympy,cccfran/sympy,postvakje/sympy,meghana1995/sympy,rahuldan/sympy,diofant/diofant,srjoglekar246/sympy,souravsingh/sympy,ahhda/sympy,Curious72/sympy,asm666/sympy,shipci/sympy,ChristinaZografou/sympy,Shaswat27/sympy,wanglongqi/sympy,MechCoder/sympy,yukoba/sympy,chaffra/sympy,emon10005/sympy,chaffra/sympy,skirpichev/omg,wyom/sympy,lindsayad/sympy,AkademieOlympia/sympy,jaimahajan1997/sympy,AkademieOlympia/sympy,wanglongqi/sympy,emon10005/sympy,atsao72/sympy,ahhda/sympy,drufat/sympy,mcdaniel67/sympy,sahilshekhawat/sympy,Titan-C/sympy,lindsayad/sympy,mcdaniel67/sympy,rahuldan/sympy,Curious72/sympy,garvitr/sympy,ahhda/sympy,Davidjohnwilson/sympy,hrashk/sympy,atsao72/sympy,bukzor/sympy,kumarkrishna/sympy,yashsharan/sympy,flacjacket/sympy,asm666/sympy,vipulroxx/sympy,jerli/sympy,pbrady/sympy,farhaanbukhsh/sympy,Gadal/sympy,sunny94/temp,cswiercz/sympy,garvitr/sympy,jamesblunt/sympy,hrashk/sympy,kumarkrishna/sympy,sahilshekhawat/sympy,abhiii5459/sympy,Davidjohnwilson/sympy,drufat/sympy,ChristinaZografou/sympy,vipulroxx/sympy,Vishluck/sympy,abhiii5459/sympy,oliverlee/sympy,AunShiLord/sympy,Sumith1896/sympy,moble/sympy,debugger22/sympy,MridulS/sympy,mafiya69/sympy,beni55/sympy,chaffra/sympy,sahilshekhawat/sympy,lidavidm/sympy,madan96/sympy,Shaswat27/sympy,hargup/sympy,skidzo/sympy,wanglongqi/sympy,farhaanbukhsh/sympy,yashsharan/sympy,pandeyadarsh/sympy,emon10005/sympy,sunny94/temp,Arafatk/sympy,kmacinnis/sympy,Titan-C/sympy,ChristinaZografou/sympy,pbrady/sympy,iamutkarshtiwari/sympy,ga7g08/sympy,kumarkrishna/sympy,Davidjohnwilson/sympy,bukzor/sympy,debugger22/sympy,postvakje/sympy,yashsharan/sympy,Mitchkoens/sympy,cccfran/sympy,MridulS/sympy,sampadsaha5/sympy,Gadal/sympy,mafiya69/sympy,shikil/sympy,liangjiaxing/sympy,Mitchkoens/sympy,kevalds51/sympy,maniteja123/sympy,oliverlee/sympy,jbbskinny/sympy,moble/sympy,hrashk/sympy,VaibhavAgarwalVA/sympy,atreyv/sympy,mcdaniel67/sympy,atreyv/sympy,saurabhjn76/sympy,Vishluck/sympy,jerli/sympy,iamutkarshtiwari/sympy,Arafatk/sympy,meghana1995/sympy,kaushik94/sympy,Mitchkoens/sympy,kaichogami/sympy,asm666/sympy,ga7g08/sympy,maniteja123/sympy,Curious72/sympy,atsao72/sympy,jbbskinny/sympy,vipulroxx/sympy,cswiercz/sympy,saurabhjn76/sympy,wyom/sympy,jbbskinny/sympy,souravsingh/sympy,jamesblunt/sympy,sampadsaha5/sympy,souravsingh/sympy,kaichogami/sympy,madan96/sympy,pbrady/sympy,toolforger/sympy,mafiya69/sympy,lindsayad/sympy,jaimahajan1997/sympy,debugger22/sympy,saurabhjn76/sympy,dqnykamp/sympy,grevutiu-gabriel/sympy,kaushik94/sympy,kevalds51/sympy,kmacinnis/sympy,ga7g08/sympy,Sumith1896/sympy,toolforger/sympy,Vishluck/sympy,abloomston/sympy,atreyv/sympy,hargup/sympy,bukzor/sympy,wyom/sympy,Gadal/sympy,AkademieOlympia/sympy,jerli/sympy,pandeyadarsh/sympy,rahuldan/sympy,lidavidm/sympy,jamesblunt/sympy,sahmed95/sympy,madan96/sympy,Designist/sympy,garvitr/sympy,maniteja123/sympy,sahmed95/sympy,oliverlee/sympy,Designist/sympy,aktech/sympy,kevalds51/sympy,kaushik94/sympy,shipci/sympy,liangjiaxing/sympy,sahmed95/sympy,VaibhavAgarwalVA/sympy,Sumith1896/sympy,MechCoder/sympy,farhaanbukhsh/sympy,yukoba/sympy,abloomston/sympy,shikil/sympy,Arafatk/sympy,cccfran/sympy,kaichogami/sympy,meghana1995/sympy,VaibhavAgarwalVA/sympy,liangjiaxing/sympy,Shaswat27/sympy,drufat/sympy,toolforger/sympy