Added pre/post setup/teardown hooks for NTestFixture subclasses.
Re-order NImageFormat usage to sort by bit depth.
Add missing const.
Add type to avoid cast mismatch for NIndexList.
Rename mkvector to nvector.
Use swizzle to implement rotate for both endian-ness.
Add pixel format conversion tests.
Expand 24bpp images to 32bpp as 24bpp isn't a supported CGBitmapContext format.
Use Image I/O constants for encoding (GIF UTI doesn't match Nano UTI).
Enable some new clang warning flags.
Added NN_TARGET_COMPILER_xxxx macros for clang/gcc/msc.
Define NN_TARGET_COMPILER_xxxx macros to the active compiler version.