Fix compatibility of set_xlabel and set_ylabel with Matplotlib 3.0
Fix compatibility of set_xlabel and set_ylabel with Matplotlib 3.0
stargaser/astropy,saimn/astropy,aleksandr-bakanov/astropy,lpsinger/astropy,lpsinger/astropy,astropy/astropy,mhvk/astropy,dhomeier/astropy,astropy/astropy,pllim/astropy,larrybradley/astropy,pllim/astropy,StuartLittlefair/astropy,lpsinger/astropy,bsipocz/astropy,saimn/astropy,lpsinger/astropy,pllim/astropy,StuartLittlefair/astropy,mhvk/astropy,stargaser/astropy,mhvk/astropy,aleksandr-bakanov/astropy,mhvk/astropy,larrybradley/astropy,bsipocz/astropy,aleksandr-bakanov/astropy,mhvk/astropy,aleksandr-bakanov/astropy,astropy/astropy,larrybradley/astropy,saimn/astropy,pllim/astropy,astropy/astropy,dhomeier/astropy,stargaser/astropy,dhomeier/astropy,MSeifert04/astropy,pllim/astropy,MSeifert04/astropy,astropy/astropy,saimn/astropy,StuartLittlefair/astropy,saimn/astropy,MSeifert04/astropy,larrybradley/astropy,dhomeier/astropy,MSeifert04/astropy,StuartLittlefair/astropy,stargaser/astropy,larrybradley/astropy,StuartLittlefair/astropy,bsipocz/astropy,lpsinger/astropy,dhomeier/astropy,bsipocz/astropy