fix distance/units test
fix distance/units test

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