parity with delaunator@3.0.1

• mprove numerical robustness
• make sure hash doesn't change size

Parity with JS delaunator@2.0.3

• fix rare race condition that produces corrupt halfedges
• improve perf on certain kinds of input
• fix race condition that produced broken triangulation
• more benchmarks

Switching to header-only library

• header-only library based on https://github.com/mapbox/hpp-skel
• unit tests
• benchmarks
• clang-format

Many thanks to @flippmoke

Initial release

• 2D Delaunay Triangulation implementation src/delaunator.h src/delaunator.cpp
• Triangulation of GeoJson points src/triangulate.cpp