Endian type check

[Ghostwalker71]

Adding endian type check to num uv sets as seen in nif xml pull req - Particle system + 20.3.0.9 support - commit - Extended support for 20.3.0.9 causes pyffi to return a missing attribute error during import within blender.

[neomonkeus]

Can you upload the stacktrace from the error.

[Ghostwalker71]

I have since rearranged the file structure and made numerous edits to my pyffi repo, so it wouldn't be a valid stack. the pull for the xml can be easily merged with the current develop branch in the niftools repo. The conflicts were minor.

[neomonkeus]

Reference niftools/nifxml#40