Fix memory leak in WCS reported in #2754
Fix memory leak in WCS reported in #2754

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