Change separation character for PhysicalType.__str__
Change separation character for PhysicalType.__str__

astropy/astropy,larrybradley/astropy,saimn/astropy,pllim/astropy,astropy/astropy,larrybradley/astropy,larrybradley/astropy,pllim/astropy,aleksandr-bakanov/astropy,StuartLittlefair/astropy,mhvk/astropy,saimn/astropy,mhvk/astropy,larrybradley/astropy,lpsinger/astropy,mhvk/astropy,pllim/astropy,lpsinger/astropy,lpsinger/astropy,StuartLittlefair/astropy,astropy/astropy,saimn/astropy,saimn/astropy,larrybradley/astropy,pllim/astropy,aleksandr-bakanov/astropy,mhvk/astropy,aleksandr-bakanov/astropy,mhvk/astropy,lpsinger/astropy,StuartLittlefair/astropy,aleksandr-bakanov/astropy,lpsinger/astropy,pllim/astropy,astropy/astropy,astropy/astropy,saimn/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy