[C++-sig] reuse C++ classes that have been wrapped with SWIG

[Ralf W. Grosse-Kunstleve]

Yes, should be possible, although I haven't tried it in a long time, but here 
are 

some old files that may still work:

http://cctbx.svn.sourceforge.net/viewvc/cctbx/trunk/boost_adaptbx/

swig_arg.hpp
swig_args_ext.cpp
tests/tst_swig_args.py
SConscript

In the SConscript look for "swig".