update release instructions to reflect needing to update contributor list
update release instructions to reflect needing to update contributor list

dhomeier/astropy,tbabej/astropy,dhomeier/astropy,dhomeier/astropy,lpsinger/astropy,joergdietrich/astropy,AustereCuriosity/astropy,DougBurke/astropy,aleksandr-bakanov/astropy,AustereCuriosity/astropy,pllim/astropy,stargaser/astropy,larrybradley/astropy,kelle/astropy,bsipocz/astropy,joergdietrich/astropy,mhvk/astropy,bsipocz/astropy,larrybradley/astropy,MSeifert04/astropy,pllim/astropy,dhomeier/astropy,tbabej/astropy,pllim/astropy,mhvk/astropy,tbabej/astropy,StuartLittlefair/astropy,tbabej/astropy,astropy/astropy,joergdietrich/astropy,lpsinger/astropy,StuartLittlefair/astropy,funbaker/astropy,AustereCuriosity/astropy,mhvk/astropy,pllim/astropy,aleksandr-bakanov/astropy,DougBurke/astropy,kelle/astropy,AustereCuriosity/astropy,kelle/astropy,DougBurke/astropy,DougBurke/astropy,MSeifert04/astropy,kelle/astropy,pllim/astropy,StuartLittlefair/astropy,funbaker/astropy,saimn/astropy,dhomeier/astropy,MSeifert04/astropy,mhvk/astropy,astropy/astropy,StuartLittlefair/astropy,funbaker/astropy,MSeifert04/astropy,joergdietrich/astropy,funbaker/astropy,tbabej/astropy,lpsinger/astropy,astropy/astropy,StuartLittlefair/astropy,saimn/astropy,joergdietrich/astropy,aleksandr-bakanov/astropy,stargaser/astropy,saimn/astropy,bsipocz/astropy,lpsinger/astropy,larrybradley/astropy,lpsinger/astropy,astropy/astropy,AustereCuriosity/astropy,larrybradley/astropy,mhvk/astropy,stargaser/astropy,stargaser/astropy,saimn/astropy,astropy/astropy,kelle/astropy,saimn/astropy,bsipocz/astropy,aleksandr-bakanov/astropy,larrybradley/astropy