functionality into cucul_set_attr().
  * Add cucul_ansi_to_attr() and cucul_argb_to_attr().
  * Rename CUCUL_COLOR_* to CUCUL_*.

0.x glue code.

just need to include <caca0.h> instead of <caca.h> and should be source-
    compatible with old versions of libcaca.

    Most of the old API works, except features and caca_sqrt(). Sprites do
    work API-wise but due to the new format they are no longer working in
    the same way.