fix spaces in docstring for polygon
fix spaces in docstring for polygon

srinathv/vispy,dchilds7/Deysha-Star-Formation,bollu/vispy,RebeccaWPerry/vispy,Eric89GXL/vispy,julienr/vispy,srinathv/vispy,RebeccaWPerry/vispy,sh4wn/vispy,bollu/vispy,jay3sh/vispy,sbtlaarzc/vispy,drufat/vispy,julienr/vispy,sh4wn/vispy,jay3sh/vispy,inclement/vispy,michaelaye/vispy,RebeccaWPerry/vispy,drufat/vispy,Eric89GXL/vispy,dchilds7/Deysha-Star-Formation,inclement/vispy,sbtlaarzc/vispy,inclement/vispy,ghisvail/vispy,jdreaver/vispy,jdreaver/vispy,dchilds7/Deysha-Star-Formation,ghisvail/vispy,michaelaye/vispy,jdreaver/vispy,bollu/vispy,kkuunnddaannkk/vispy,QuLogic/vispy,drufat/vispy,kkuunnddaannkk/vispy,QuLogic/vispy,srinathv/vispy,michaelaye/vispy,sh4wn/vispy,julienr/vispy,QuLogic/vispy,sbtlaarzc/vispy,kkuunnddaannkk/vispy,jay3sh/vispy,ghisvail/vispy,Eric89GXL/vispy