Merge branch 'FlorianRudolf/fix-cmake' into FlorianRudolf/feature-algorithm-geometry-generator

Conflicts:
	CMakeLists.txt
	pyviennamesh/CMakeLists.txt
	src/CMakeLists.txt
base_geometry_generator prototype
Merge branch 'FlorianRudolf/feature-parameter-interface-improvement' into FlorianRudolf/feature-algorithm-geometry-generator
further implementation on base_geometry_generator infrastructure
file cleanup/restructure (interpreter moved to utils, ...)
adapted to new defines (VIENNAMESH_WITH_NETGEN_OPENCASCADE)
added vec1, vec2 and vec3 typedefs (same as point_Xd), added base_brep_geometry_generator, added brep_2d_geometry_generator, some infrastructure changes, added error handling, added support for default values
Merge branch 'FlorianRudolf/fix-cmake' into next
Merge branch 'FlorianRudolf/feature-algorithm-geometry-generator' into next

Conflicts:
	include/viennamesh/core/basic_parameters.hpp