Remove requires_2to3 from asdf/setup_package.py
Remove requires_2to3 from asdf/setup_package.py

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