Resolve "New source type: surface of a region in the mesh should emit photons randomly in the direction of the surface normal"
Highlights:
- Implemented SurfaceSourceBuilder and CylinderSurfaceSourceBuilder (as issue suggest)
- Improved performance of FiberCone by computing spin matrix only once
- Centralized some functions (spin matrix, is point in tetra, ...)
- Fixed some minor bugs (code and CMake)
Closes #146 (closed)