Update sigma_clip doctest
Update sigma_clip doctest

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