[ab] [FIX] make lispbuilder-sdl-ttf "less free"

[Luke J Crook]

Luke J Crook wrote:
> I'm going to have to add a *generation* counter. Each time the font
> library is closed the generation counter is increased. Then add a test
> in the CFFI finalization method to test if the font to be free'd was
> created in the current *generation*. If it was not then the font cannot
> be freed.

This also needs to be added to SURFACES.  Because by default SDL_Quit is
never called this bug has been hidden thus far.

- Luke