Replacing bob.ip.base.FaceEyesNorm

This is next chapter on our C++ deprecation crusade (https://gitlab.idiap.ch/groups/bob/-/milestones/4#tab-issues).

In this MR I'm deprecating a VERY sensible part of our pipeline the C++ bob.ip.base.FaceEyesNorm.

I've implemented in python an EXACT implementation of our face alignment in pure python. Amazing, this was reduced to less than 100 lines of code (https://gitlab.idiap.ch/bob/bob.bio.face/-/blob/new-cropper/bob/bio/face/preprocessor/Base.py#L134).

Furthermore, I've addressed the aliasing issue reported in #74 by changing the bi-linear interpolation to a bi-cubic interpolation (thanks @lcolbois).

Follow an example of our old crop (bilinear) and the new crop (bicubic), side by side (final crop with 112x112, arcface coordinates).

Follow also a pair of images from one of our test cases.

New test case Crop

Old test case crop

I still need to run some FR experiments on it and change some other face cropper classes.

With that, we can start moving forward towards detaching bob.ip.base from this package.

This is still a WIP

ping @mguenther, @linghuy @lcolbois @amohammadi @ydayer @flavio.tarsetti

bob/bio/face/database/lfw.py

@@ -336,7 +336,7 @@ class LFWDatabase(Database):
 
         """
         if self.protocol[0] != "o":
-            return [0]
+            return []
 
         # return a list of samplesets for each enrollment image and each known unknown training sample
         enrollmentset = self.references()