- added simple utility print_materials.cc 
 - started to implement averaging materials for surfaces
    - issue with ILDExDet geometry and assemblies ...

   - use in DDRec::SurfaceMaterial
 - added explicit method double * const_array() to  DDSurfaces::Vector3D
   in order to fix issue  with conversion operator that is not 
   recognized by some compilers

 - added DDSurfaces to Doxygen
 - cleaned up DDSurfaces to have only 
   pure abstract base classes (interfaces)

   - no superseeded by pure abstract ISurface and IMaterial

     - draw sensitive surfaces in red and helper surfaces in gray
     - protect against missing lcio input file
  - reduced printout from VolumeManager  (changed INFO to DEBUG)

   access to cylinider radius for the tracking

   as this causes template lookup errors on some machines :
   -> use explicit conversion with to<T>() instead

     to provide some hierarchical strucutre to the geometry

   ( copy did not work ) 

    - ILD examples for now include internal header DetectorInterna.h
  - minor fixes for printing ISurfaces
  - added drawing of z-planes inside tubes (TPC endcap)
  - tried to add copy c'tor foe extension object VolSurfaceList
     -> causes seg. fault ...
     

Hopefully I got the assemblies right now. Assembly test added in examples/ClientTests. Please see also doc/release.notes

 - added drawing for cylinders in Surface.ccp/teve_display
 - added copy ctor and assignment to Vector3D
 -...

   projections of surfaces

     #define use_layer_assembly 1
   results in a seg fault when running:
     ildex_simu  file:../ILDExDet/compact/ILDEx.xml file:../ILDExDet/compact/geant4.xml ../ILDExSimu/run1.mac

This way, one hour bug hunting is skipped.

 - added drawing of LCIO events to teve_display 
   - so far only SimTrackerHits ( tbc) 

 - new method Surface::getVertices() (only planes so far)
 - added some convenient methods to Vector3D

 - include in test_surfaces.cc
 - added Vector3D::fill( double, double, double )