DOC: improve false alarm probability docs
DOC: improve false alarm probability docs

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