Add README to examples/notebooks, fixes #8443
Add README to examples/notebooks, fixes #8443

Tell users to run ``ipython notebook``, not just ``ipython``.

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