FrameBuffer with multisampling

Hello all,

After working with post-processing shaders, I found out that framebuffers don't use msaa (only the default one).
It was a very annoying discovery so I decided to modify the FrameBuffer class and add the ability to automatically use multisampling if graphic card is able to.

It's quite brute coded but everything should be there before refactoring !
I know it uses opengl extensions, so for compatibility this is not the best thing, but because it switches automatically to multisampling if and only if available, it shouldn't be a problem for non-capable graphic cards.
(perhaps frameBuffer multisampling should it be an option in FrameBuffer constructor or get the msaa variable of configuration ?)
What do you think ?