Alphashapes and Python bindings
* converted alphashapes2d to the new format
* added Python bindings for alphashapes
* added sample alphashapes.py that dynamically distinguishes between 2D and 3D
add_subdirectory (alphashapes)
#add_subdirectory (ar-vineyard)
add_subdirectory (cech-complex)
add_subdirectory (consistency)
add_subdirectory (cohomology)
add_subdirectory (fitness)
#add_subdirectory (grid)
add_subdirectory (triangle)
add_subdirectory (poincare)
add_subdirectory (rips)