Add regression tests for biweight_location
Add regression tests for biweight_location

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