Update documentation to reflect that all dimensionless scalars can be converted
Update documentation to reflect that all dimensionless scalars can be converted

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