[Namespaces changes]

vert->vertex 

clean up of some namespaces to comply the following naming:

Complexes (3 letters namespaces):
order 0 (point cloud    ) :vrt
order 1 (edge meshes)     :edg
order 2 (triangle meshes) :tri
order 3 (triangle meshes) :tet

Simplexes (4 letters namespaces):
order 0 (vertex)      :vert 
order 1 (edge)        :edge 
order 2 (triangle)    :triangle
order 3 (tetrahedron) :tetrahedron

vcg/simplex/vertexplus/component_ocf.h

@@ -97,7 +97,7 @@ Mainly the trick here is to store a base pointer in each simplex...
 #include <limits>
 
 namespace vcg {
-  namespace vert {
+  namespace vertex {
 /*
 All the Components that can be added to a vertex should be defined in the namespace vert: