some small lint improvements
some small lint improvements

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