Request: Support Xcode Quick Look Debugging

[Michael-Lfx]

It's convenient for multimedia developers to view the content of texture using Xcode Quick Look Debugging without capturing the whole gpu frame which can spend a few seconds for replaying a complex frame.

Maybe the following code is acceptable for a temp debug session.

TextureLoadDesc textureDesc = {};
textureDesc.pFileName = "QuickLookTest";
textureDesc.ppTexture = &pDebugTexture;
textureDesc.mContainer = TEXTURE_CONTAINER_JPG;
addResource(&textureDesc, NULL);
// ...
waitForAllResourceLoads();

TextureXcodeQuickLook* quickLook = [[TextureXcodeQuickLook alloc] initWithTexture:pDebugTexture];
printf("%p\n", quickLook); //meaningless, just for avoiding compile warning

It looks like the following debug screen capture of demo 01_Transformations.