Fix for detached polygons when projecting.
Fix for detached polygons when projecting.

Work-around for mbostock/d3#1558.

GerHobbelt/d3-geo-projection,jswiss/d3-geo-projection,emilbayes/d3-geo-projection,Fil/d3-geo-projection,paulkogel/d3-geo-projection,cbtpro/d3-geo-projection,Fil/d3-geo-projection