- change mesh_calc_normals to set vertices with len(no)==0

to normalised coordinate (convention in blender, helps with
   halo)
 - removed vertexnormals(), vertexnormals_mesh()
 - removed CTX_NO_NOR_RECALC (always assume already calculated)
 - change NMesh.c to call mesh_calc_normals
 - chance load_editMesh to call mesh_calc_normals after done
   converting instead of using editmesh normals
 - update recalc_editnormals to also calc vertex normals (whats
   4 more adds and a sqrt among friends)

Its hard to believe, but it just might be the case that there
are only two places mesh normals are calculated now (renderer
and kernel)

source/blender/include/BIF_meshtools.h

@@ -38,7 +38,6 @@ extern void join_mesh(void);
 extern void fasterdraw(void);
 extern void slowerdraw(void);
 
-extern void vertexnormals_mesh(Mesh *me);
 extern void sort_faces(void);