add test for unitless matching
add test for unitless matching

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