add affine transform classes to __all__
add affine transform classes to __all__

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