restricted operators to + and -
restricted operators to + and -

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