implement LBP rotation-invariant version

[johnnychen94]

250x faster than the ImageFeatures version 🚀

The secret is to pre-calculate the encoding table.

using ImageFeatures, TestImages, ImageCore

img = float32.(testimage("camera"));

@btime lbp($img, $lbp_rotation_invariant); # 328.715 ms (11010062 allocations: 506.00 MiB)
@btime lbp_ri($img); # 1.408 ms (8 allocations: 2.50 MiB)

[codecov]

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