Bigger terrain with mountain features

...rst_person_euler/camera_controller_first_person_euler.cpp

...rst_person_euler/camera_controller_first_person_euler.hpp

projet-code/scenes_inf443/base/base.exe

projet-code/scenes_inf443/base/src/scene.cpp

projet-code/scenes_inf443/base/src/scene.hpp

projet-code/scenes_inf443/base/src/terrain.cpp