Remove _perform_clip and _perform_sigclip_noaxis methods
Remove _perform_clip and _perform_sigclip_noaxis methods

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