Update guess func docs and improve/expand code comments [skip ci]
Update guess func docs and improve/expand code comments [skip ci]

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