Fix linking to multivariate_normal [docs only]
Fix linking to multivariate_normal [docs only]

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