Dr/csg linear rotate extrudes

CMakeLists.txt

src/csg/impl/csg.cpp

src/csg/impl/csg_types.hpp

src/csg/impl/levelset_2d.cpp

src/csg/impl/levelset_3d.cpp

src/csg/impl/parser.cpp

src/csg/meson.build

src/csg/tests/levelset/boolean.t.cpp

src/csg/tests/levelset/extrude.t.cpp

src/csg/tests/levelset/transform.t.cpp

src/csg/tests/meson.build

src/csg/tests/parser/boolean.t.cpp

src/csg/tests/parser/extrude.t.cpp

src/csg/tests/parser/nest.cpp

src/csg/tests/parser/transform.t.cpp