Ignore fast palette when dithering
Variable dithering level, --floyd=0.5
Warnings--
It's safe to free(NULL)
Stricter types
Removed C99isms
Clearer code for catching invalid pointers
Release 2.0
-D doesn't build on OSX Lion
Merge pull request #47 from PatrickHeneise/master

-D doesn't build on OSX Lion
Tweaked Makefile for building on OS X

Fix for 2.x
Posterize option
Restored include for USE_SSE macro
C89
Deleted unused struct
USE_SSE opt-in
Simplified optimization flags
SunOS compatibility

Fixes #49
Add include directories conditionally to avoid warnings
PIC in DLL