Update to 2.0.18:

Ver 2.0.18 - Sun Dec 21 08:38:20 PST 2008

* libtool update for dependencies
* MSVC C89 variable hoisting to enable MSVC compile (sweetlilmre)
* addition of VC9 (Visual Studio 2008) project file (sweetlilmre)
* update to MinGW make file (Sergio Padrino, sweetlilmre)
* fix uninitialised variables in _putPixelAlpha() (Paul Pedriana)
* reverted to original alpha routine in _putPixelAlpha() as new one was causing issues in 16bbp
  new routine #define has been renamed to EXPERIMENTAL_ALPHA_PIXEL_ROUTINE
  original is now DEFAULT_ALPHA_PIXEL_ROUTINE
* added colorkey handling patch to rotozoom (Sergio Padrino)
* downgraded optimization to -O for asm compatibility with gcc4

Ver 2.0.17 - Sun Jun  1 15:39:38 EDT 2008

* hline/vline clipping and swap-logic fixed
* clipping box dimension check added and clipping-checks optimized
* TestFonts program updated
* Updated documentation on cross-compilation, AMD64
* Fixed circleColor overdraw
* Added arcColor routine
* Added polygonColorMT and polygonTextureMT routines
* Updated 32bit alpha blending routine

(wiz)