added changelog entry for galactocentric
added changelog entry for galactocentric

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