Biweight_midvariance docstring update.
Biweight_midvariance docstring update.

Clarified use of n, the sample size. Issue #3036.

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