clean up if/else structures and be more consistent
clean up if/else structures and be more consistent

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