combinatorics/partitions: Added routine to compute RGS of a partition.
combinatorics/partitions: Added routine to compute RGS of a
partition.

Signed-off-by: Saptarshi Mandal <13ec3c7bab52575f3a0cda6406c76269cc13b041@gmail.com>

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