library, so we can have several or none of them at some time.
  * sdl.c imlib.c: allow to save images that weren't created using the
    current codec.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/libpipi/trunk@2629 92316355-f0b4-4df1-b90c-862c8a59935f