editing fixes nddata/index
editing fixes nddata/index

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