docs/outreach.txt: Update links, delete cruft
docs/outreach.txt: Update links, delete cruft

The outreach.txt file (linked directly from index.txt) is outdated.
Update the links to the SymPy Papers page and our logos, delete the
section about GSoC (as it's covered already in aboutus.txt) and delete
the list of blogs/magazines mentioning SymPy in favor of just a link to
the wiki.

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