refactor into include folder

.vscode/settings.json

CMakeLists.txt

include/contourize.h

include/edge.h

include/intersections.h

include/orientation.h

include/point.h

include/static_vector.h

include/triangle.h

include/triangle_edges.h

include/triangulation.h

include/union.h

src/shapes/triangle.cpp

src/triangulation/triangulation.cpp

src/union.cpp

src/utilities/contourize.cpp

src/utilities/intersections.cpp

src/utilities/orientation.cpp

src/utilities/triangulation.cpp

tests/unit_tests/contourize_tests.cpp