[Amibe] DistanceMetric: replace setSizeInf by setScaling

During refine and decimating we scale the metric to sqrt(2). Before this
commit only the sizeInf was scaled so the it was buggy around points and
beams specified in the DistanceMetric class.
[Amibe] ImproveVertexValence: do 55 pattern after alternate pattern
[Amibe] ImproveVertexValence: remove swap 3D check

It forbid to downgrade the quality of triangles and we want to do it.
[Amibe] ImproveVertexValence: allow to collapse to a non-manifold vertex