M Principal_component_analysis/include/CGAL/linear_least_squares_fitting_segments_2.h
M Principal_component_analysis/include/CGAL/linear_least_squares_fitting_triangles_2.h
M Principal_component_analysis/include/CGAL/centroid.h
M Principal_component_analysis/examples/Principal_component_analysis/linear_least_squares_fitting_segments.cpp
M Principal_component_analysis/examples/Principal_component_analysis/linear_least_squares_fitting_triangles.cpp
M Principal_component_analysis/examples/Principal_component_analysis/linear_least_squares_fitting.cpp
Doc: added definitions, did many fixes.
IMPORTANT: sylvain: double-check the definitions, and precise the dimension and types available for each of your function.
important change: I suggest to rename the function bounding_box to axis_aligned_bounding_box (min case later you will hack on the general one).