Allegro.png

I am now going to prepare first archives to Aminet.

Known issues:
* 16-bit gfx look wrong on most systems

It is PITA to support 16-bit modes when CGX has no functions to draw 16-bit pixel arrays. I maybe look at this later.

Building a shared library is under investigation. I dont know if Allegro is suitable to that and extracting jump table is boring as ever.