Updated SDL's YUV support, many thanks to Adrien Descamps

New functions get and set the YUV colorspace conversion mode:
	SDL_SetYUVConversionMode()
	SDL_GetYUVConversionMode()
	SDL_GetYUVConversionModeForResolution()

SDL_ConvertPixels() converts between all supported RGB and YUV formats, with SSE acceleration for converting from planar YUV formats (YV12, NV12, etc) to common RGB/RGBA formats.

Added a new test program, testyuv, to verify correctness and speed of YUV conversion functionality.

Xcode-iOS/Test/Info.plist

@@ -22,7 +22,5 @@
 	<string>????</string>
 	<key>CFBundleVersion</key>
 	<string>1.0</string>
-	<key>NSMainNibFile</key>
-	<string></string>
 </dict>
 </plist>