fix face orientation "Re-Orient all faces coherently"

[christian-rauch]

This fixes the face orientation of the SDH finger meshes.
Done with MeshLab: "Filters" -> "Normals, Curvatures and Orientation" -> "Re-Orient all faces coherently"

[fmessmer]

@christian-rauch
did you experience any kind of problems with the current meshes?
when displaying the face normals of the current (indigo_dev) meshes in blender, they already seem to be oriented consistently - outward-facing.
I'm happy to merge this PR, but I can't see the "diff"...also, if there actually was something to be fixed, could you also fix it for the other meshes, i.e. palm, knuckle,....

[christian-rauch]

I experienced issues when rendering the meshes in a normal OpenGL renderer. The finger meshes do no reflect light, e.g. they do not respect the light source:

After opening and exporting the finger.stl and finger_tip.stl meshes with MeshLab, I obtain a more realistic rendering:

As it turns out, just exporting the mesh in MeshLab without applying any filter already produces this result. The face normals seem not to be the issue. Since the files are binary, I cannot tell the changes that are applied by MeshLab.

[fmessmer]

thanks @christian-rauch for clarification
I remember that there has been times were opening and re-exporting meshes through meshlab (or blender) helped with some issues related to MoveIt!, too