fix number -> string formatting bug
fix number -> string formatting bug

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