Added GLFW initialization and loop
Added GLFW initialization and loop

We use GLFW to create an OpenGL buffer with the right profile, and then
create a window. We set up a rendering/inputs handling loop. At the
end, we close the window and release the OpenGL context.


Former-commit-id: 061c4f39fc6fe32c264e38e15d15083a98745215
kosua20/GL_Template,kosua20/GL_Template