Add a Versions of Constants section to constants doc
Add a Versions of Constants section to constants doc

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