Fix heading level in table docs
Fix heading level in table docs

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