Modified file include accordingly

Boundary layer c++ objects are created in python with swig and are manipulated by the interface. The initial condition of the viscous solver was changed. All test cases have been adapted. A decrease in the number of iterations is globally observed. Results are slightly improved especially for the RAE validation case.

Fixed API, dart interface and prevented segfault if the number of sections is not imposed correctly.

Contains 2D and 3D developements as well as the api.