Merge image related changes from the render branch. This includes the image

tile cache code in imbuf, but it is not hooked up to the render engine.


Imbuf module: some small refactoring and removing a lot of unused or old code
(about 6.5k lines).

* Added a ImFileType struct with callbacks to make adding an file format type,
  or making changes to the API easier.
* Move imbuf init/exit code into IMB_init()/IMB_exit() functions.
* Increased mipmap levels from 10 to 20, you run into this limit already with
  a 2k image.
* Removed hamx, amiga, anim5 format support.
* Removed colormap saving, only simple colormap code now for reading tga.
* Removed gen_dynlibtiff.py, editing this is almost as much work as just
  editing the code directly.
* Functions removed that were only used for sequencer plugin API:
  IMB_anim_nextpic, IMB_clever_double, IMB_antialias, IMB_gamwarp,
  IMB_scalefieldImBuf, IMB_scalefastfieldImBuf, IMB_onethird, IMB_halflace,
  IMB_dit0, IMB_dit2, IMB_cspace
* Write metadata info into OpenEXR images. Can be viewed with the command
  line utility 'exrheader'

For the image tile cache code, see this page:
http://wiki.blender.org/index.php/Dev:2.5/Source/Imaging/ImageTileCache

source/gameengine/GamePlayer/ghost/GPG_ghost.cpp

@@ -376,11 +376,7 @@ int main(int argc, char** argv)
 
 	GEN_init_messaging_system();
 
-#ifdef WITH_QUICKTIME
-	quicktime_init();
-#endif
-
-	libtiff_init();
+	IMB_init();
  
 	// Parse command line options
 #ifndef NDEBUG