Merge pull request #15 from mborne/master

Issue 13 : Invalid Line make distance function to crash
Merge pull request #16 from mborne/master

specific WKT for triangles (previously POLYGON((...)))
force orientation for outer ring in CGAL::Polygon_with_holes_2<Kernel> Polygon::toPolygon_with_holes_2() const
Merge branch 'master' of https://github.com/Oslandia/SFCGAL