[AD] Addons and al_free and non-public functions

[Pavel Sountsov <slabode@xxxxxxxxxx>]

I'm a little confused about when to use al_free/al_malloc and the 
non-existent al_realloc (can someone add it in?) in the addons. Should 
addons use those functions preferentially? How about the core, should 
it use those instead of _AL_MALLOC and the like?

Also, when I was removing ALLEGRO_PRIM_COLOR I noticed that I had to 
use  the  _al_add_exit_func function, which is naturally not a part of 
the public API. I copied this usage from the font addon, and I'm sure 
many other addons have something like this too. What's our policy about 
using these non-public API functions in the addons? Should we just make 
many of those functions public? Or perhaps because these addons are 
bundled, they get special privileges? I also thought that using the 
non-public API resulted in issues with dynamic libraries (since the 
non-public API's are not wrapped in the magic macro).

-SiegeLord